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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 244 | chris | 1 | /* |
| 2 | * jdmarker.c |
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| 3 | * |
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| 4 | * Copyright (C) 1991-1998, Thomas G. Lane. |
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| 5 | * This file is part of the Independent JPEG Group's software. |
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| 6 | * For conditions of distribution and use, see the accompanying README file. |
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| 7 | * |
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| 8 | * This file contains routines to decode JPEG datastream markers. |
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| 9 | * Most of the complexity arises from our desire to support input |
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| 10 | * suspension: if not all of the data for a marker is available, |
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| 11 | * we must exit back to the application. On resumption, we reprocess |
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| 12 | * the marker. |
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| 13 | */ |
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| 14 | |||
| 15 | #define JPEG_INTERNALS |
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| 16 | #include "jinclude.h" |
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| 17 | #include "jpeglib.h" |
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| 18 | |||
| 19 | |||
| 20 | typedef enum { /* JPEG marker codes */ |
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| 21 | M_SOF0 = 0xc0, |
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| 22 | M_SOF1 = 0xc1, |
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| 23 | M_SOF2 = 0xc2, |
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| 24 | M_SOF3 = 0xc3, |
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| 25 | |||
| 26 | M_SOF5 = 0xc5, |
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| 27 | M_SOF6 = 0xc6, |
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| 28 | M_SOF7 = 0xc7, |
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| 29 | |||
| 30 | M_JPG = 0xc8, |
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| 31 | M_SOF9 = 0xc9, |
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| 32 | M_SOF10 = 0xca, |
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| 33 | M_SOF11 = 0xcb, |
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| 34 | |||
| 35 | M_SOF13 = 0xcd, |
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| 36 | M_SOF14 = 0xce, |
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| 37 | M_SOF15 = 0xcf, |
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| 38 | |||
| 39 | M_DHT = 0xc4, |
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| 40 | |||
| 41 | M_DAC = 0xcc, |
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| 42 | |||
| 43 | M_RST0 = 0xd0, |
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| 44 | M_RST1 = 0xd1, |
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| 45 | M_RST2 = 0xd2, |
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| 46 | M_RST3 = 0xd3, |
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| 47 | M_RST4 = 0xd4, |
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| 48 | M_RST5 = 0xd5, |
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| 49 | M_RST6 = 0xd6, |
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| 50 | M_RST7 = 0xd7, |
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| 51 | |||
| 52 | M_SOI = 0xd8, |
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| 53 | M_EOI = 0xd9, |
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| 54 | M_SOS = 0xda, |
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| 55 | M_DQT = 0xdb, |
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| 56 | M_DNL = 0xdc, |
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| 57 | M_DRI = 0xdd, |
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| 58 | M_DHP = 0xde, |
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| 59 | M_EXP = 0xdf, |
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| 60 | |||
| 61 | M_APP0 = 0xe0, |
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| 62 | M_APP1 = 0xe1, |
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| 63 | M_APP2 = 0xe2, |
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| 64 | M_APP3 = 0xe3, |
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| 65 | M_APP4 = 0xe4, |
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| 66 | M_APP5 = 0xe5, |
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| 67 | M_APP6 = 0xe6, |
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| 68 | M_APP7 = 0xe7, |
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| 69 | M_APP8 = 0xe8, |
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| 70 | M_APP9 = 0xe9, |
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| 71 | M_APP10 = 0xea, |
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| 72 | M_APP11 = 0xeb, |
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| 73 | M_APP12 = 0xec, |
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| 74 | M_APP13 = 0xed, |
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| 75 | M_APP14 = 0xee, |
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| 76 | M_APP15 = 0xef, |
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| 77 | |||
| 78 | M_JPG0 = 0xf0, |
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| 79 | M_JPG13 = 0xfd, |
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| 80 | M_COM = 0xfe, |
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| 81 | |||
| 82 | M_TEM = 0x01, |
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| 83 | |||
| 84 | M_ERROR = 0x100 |
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| 85 | } JPEG_MARKER; |
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| 86 | |||
| 87 | |||
| 88 | /* Private state */ |
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| 89 | |||
| 90 | typedef struct { |
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| 91 | struct jpeg_marker_reader pub; /* public fields */ |
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| 92 | |||
| 93 | /* Application-overridable marker processing methods */ |
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| 94 | jpeg_marker_parser_method process_COM; |
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| 95 | jpeg_marker_parser_method process_APPn[16]; |
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| 96 | |||
| 97 | /* Limit on marker data length to save for each marker type */ |
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| 98 | unsigned int length_limit_COM; |
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| 99 | unsigned int length_limit_APPn[16]; |
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| 100 | |||
| 101 | /* Status of COM/APPn marker saving */ |
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| 102 | jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */ |
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| 103 | unsigned int bytes_read; /* data bytes read so far in marker */ |
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| 104 | /* Note: cur_marker is not linked into marker_list until it's all read. */ |
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| 105 | } my_marker_reader; |
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| 106 | |||
| 107 | typedef my_marker_reader * my_marker_ptr; |
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| 108 | |||
| 109 | |||
| 110 | /* |
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| 111 | * Macros for fetching data from the data source module. |
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| 112 | * |
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| 113 | * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect |
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| 114 | * the current restart point; we update them only when we have reached a |
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| 115 | * suitable place to restart if a suspension occurs. |
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| 116 | */ |
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| 117 | |||
| 118 | /* Declare and initialize local copies of input pointer/count */ |
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| 119 | #define INPUT_VARS(cinfo) \ |
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| 120 | struct jpeg_source_mgr * datasrc = (cinfo)->src; \ |
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| 121 | const JOCTET * next_input_byte = datasrc->next_input_byte; \ |
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| 122 | size_t bytes_in_buffer = datasrc->bytes_in_buffer |
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| 123 | |||
| 124 | /* Unload the local copies --- do this only at a restart boundary */ |
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| 125 | #define INPUT_SYNC(cinfo) \ |
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| 126 | ( datasrc->next_input_byte = next_input_byte, \ |
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| 127 | datasrc->bytes_in_buffer = bytes_in_buffer ) |
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| 128 | |||
| 129 | /* Reload the local copies --- used only in MAKE_BYTE_AVAIL */ |
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| 130 | #define INPUT_RELOAD(cinfo) \ |
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| 131 | ( next_input_byte = datasrc->next_input_byte, \ |
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| 132 | bytes_in_buffer = datasrc->bytes_in_buffer ) |
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| 133 | |||
| 134 | /* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available. |
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| 135 | * Note we do *not* do INPUT_SYNC before calling fill_input_buffer, |
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| 136 | * but we must reload the local copies after a successful fill. |
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| 137 | */ |
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| 138 | #define MAKE_BYTE_AVAIL(cinfo,action) \ |
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| 139 | if (bytes_in_buffer == 0) { \ |
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| 140 | if (! (*datasrc->fill_input_buffer) (cinfo)) \ |
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| 141 | { action; } \ |
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| 142 | INPUT_RELOAD(cinfo); \ |
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| 143 | } |
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| 144 | |||
| 145 | /* Read a byte into variable V. |
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| 146 | * If must suspend, take the specified action (typically "return FALSE"). |
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| 147 | */ |
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| 148 | #define INPUT_BYTE(cinfo,V,action) \ |
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| 149 | MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ |
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| 150 | bytes_in_buffer--; \ |
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| 151 | V = GETJOCTET(*next_input_byte++); ) |
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| 152 | |||
| 153 | /* As above, but read two bytes interpreted as an unsigned 16-bit integer. |
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| 154 | * V should be declared unsigned int or perhaps INT32. |
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| 155 | */ |
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| 156 | #define INPUT_2BYTES(cinfo,V,action) \ |
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| 157 | MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ |
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| 158 | bytes_in_buffer--; \ |
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| 159 | V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \ |
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| 160 | MAKE_BYTE_AVAIL(cinfo,action); \ |
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| 161 | bytes_in_buffer--; \ |
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| 162 | V += GETJOCTET(*next_input_byte++); ) |
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| 163 | |||
| 164 | |||
| 165 | /* |
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| 166 | * Routines to process JPEG markers. |
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| 167 | * |
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| 168 | * Entry condition: JPEG marker itself has been read and its code saved |
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| 169 | * in cinfo->unread_marker; input restart point is just after the marker. |
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| 170 | * |
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| 171 | * Exit: if return TRUE, have read and processed any parameters, and have |
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| 172 | * updated the restart point to point after the parameters. |
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| 173 | * If return FALSE, was forced to suspend before reaching end of |
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| 174 | * marker parameters; restart point has not been moved. Same routine |
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| 175 | * will be called again after application supplies more input data. |
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| 176 | * |
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| 177 | * This approach to suspension assumes that all of a marker's parameters |
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| 178 | * can fit into a single input bufferload. This should hold for "normal" |
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| 179 | * markers. Some COM/APPn markers might have large parameter segments |
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| 180 | * that might not fit. If we are simply dropping such a marker, we use |
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| 181 | * skip_input_data to get past it, and thereby put the problem on the |
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| 182 | * source manager's shoulders. If we are saving the marker's contents |
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| 183 | * into memory, we use a slightly different convention: when forced to |
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| 184 | * suspend, the marker processor updates the restart point to the end of |
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| 185 | * what it's consumed (ie, the end of the buffer) before returning FALSE. |
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| 186 | * On resumption, cinfo->unread_marker still contains the marker code, |
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| 187 | * but the data source will point to the next chunk of marker data. |
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| 188 | * The marker processor must retain internal state to deal with this. |
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| 189 | * |
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| 190 | * Note that we don't bother to avoid duplicate trace messages if a |
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| 191 | * suspension occurs within marker parameters. Other side effects |
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| 192 | * require more care. |
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| 193 | */ |
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| 194 | |||
| 195 | |||
| 196 | LOCAL(boolean) |
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| 197 | get_soi (j_decompress_ptr cinfo) |
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| 198 | /* Process an SOI marker */ |
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| 199 | { |
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| 200 | int i; |
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| 201 | |||
| 202 | TRACEMS(cinfo, 1, JTRC_SOI); |
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| 203 | |||
| 204 | if (cinfo->marker->saw_SOI) |
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| 205 | ERREXIT(cinfo, JERR_SOI_DUPLICATE); |
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| 206 | |||
| 207 | /* Reset all parameters that are defined to be reset by SOI */ |
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| 208 | |||
| 209 | for (i = 0; i < NUM_ARITH_TBLS; i++) { |
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| 210 | cinfo->arith_dc_L[i] = 0; |
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| 211 | cinfo->arith_dc_U[i] = 1; |
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| 212 | cinfo->arith_ac_K[i] = 5; |
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| 213 | } |
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| 214 | cinfo->restart_interval = 0; |
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| 215 | |||
| 216 | /* Set initial assumptions for colorspace etc */ |
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| 217 | |||
| 218 | cinfo->jpeg_color_space = JCS_UNKNOWN; |
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| 219 | cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */ |
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| 220 | |||
| 221 | cinfo->saw_JFIF_marker = FALSE; |
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| 222 | cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */ |
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| 223 | cinfo->JFIF_minor_version = 1; |
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| 224 | cinfo->density_unit = 0; |
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| 225 | cinfo->X_density = 1; |
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| 226 | cinfo->Y_density = 1; |
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| 227 | cinfo->saw_Adobe_marker = FALSE; |
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| 228 | cinfo->Adobe_transform = 0; |
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| 229 | |||
| 230 | cinfo->marker->saw_SOI = TRUE; |
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| 231 | |||
| 232 | return TRUE; |
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| 233 | } |
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| 234 | |||
| 235 | |||
| 236 | LOCAL(boolean) |
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| 237 | get_sof (j_decompress_ptr cinfo, boolean is_prog, boolean is_arith) |
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| 238 | /* Process a SOFn marker */ |
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| 239 | { |
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| 240 | INT32 length; |
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| 241 | int c, ci; |
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| 242 | jpeg_component_info * compptr; |
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| 243 | INPUT_VARS(cinfo); |
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| 244 | |||
| 245 | cinfo->progressive_mode = is_prog; |
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| 246 | cinfo->arith_code = is_arith; |
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| 247 | |||
| 248 | INPUT_2BYTES(cinfo, length, return FALSE); |
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| 249 | |||
| 250 | INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE); |
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| 251 | INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE); |
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| 252 | INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE); |
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| 253 | INPUT_BYTE(cinfo, cinfo->num_components, return FALSE); |
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| 254 | |||
| 255 | length -= 8; |
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| 256 | |||
| 257 | TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker, |
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| 258 | (int) cinfo->image_width, (int) cinfo->image_height, |
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| 259 | cinfo->num_components); |
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| 260 | |||
| 261 | if (cinfo->marker->saw_SOF) |
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| 262 | ERREXIT(cinfo, JERR_SOF_DUPLICATE); |
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| 263 | |||
| 264 | /* We don't support files in which the image height is initially specified */ |
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| 265 | /* as 0 and is later redefined by DNL. As long as we have to check that, */ |
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| 266 | /* might as well have a general sanity check. */ |
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| 267 | if (cinfo->image_height <= 0 || cinfo->image_width <= 0 |
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| 268 | || cinfo->num_components <= 0) |
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| 269 | ERREXIT(cinfo, JERR_EMPTY_IMAGE); |
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| 270 | |||
| 271 | if (length != (cinfo->num_components * 3)) |
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| 272 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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| 273 | |||
| 274 | if (cinfo->comp_info == NULL) /* do only once, even if suspend */ |
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| 275 | cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small) |
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| 276 | ((j_common_ptr) cinfo, JPOOL_IMAGE, |
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| 277 | cinfo->num_components * SIZEOF(jpeg_component_info)); |
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| 278 | |||
| 279 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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| 280 | ci++, compptr++) { |
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| 281 | compptr->component_index = ci; |
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| 282 | INPUT_BYTE(cinfo, compptr->component_id, return FALSE); |
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| 283 | INPUT_BYTE(cinfo, c, return FALSE); |
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| 284 | compptr->h_samp_factor = (c >> 4) & 15; |
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| 285 | compptr->v_samp_factor = (c ) & 15; |
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| 286 | INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE); |
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| 287 | |||
| 288 | TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT, |
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| 289 | compptr->component_id, compptr->h_samp_factor, |
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| 290 | compptr->v_samp_factor, compptr->quant_tbl_no); |
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| 291 | } |
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| 292 | |||
| 293 | cinfo->marker->saw_SOF = TRUE; |
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| 294 | |||
| 295 | INPUT_SYNC(cinfo); |
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| 296 | return TRUE; |
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| 297 | } |
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| 298 | |||
| 299 | |||
| 300 | LOCAL(boolean) |
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| 301 | get_sos (j_decompress_ptr cinfo) |
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| 302 | /* Process a SOS marker */ |
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| 303 | { |
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| 304 | INT32 length; |
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| 305 | int i, ci, n, c, cc; |
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| 306 | jpeg_component_info * compptr; |
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| 307 | INPUT_VARS(cinfo); |
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| 308 | |||
| 309 | if (! cinfo->marker->saw_SOF) |
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| 310 | ERREXIT(cinfo, JERR_SOS_NO_SOF); |
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| 311 | |||
| 312 | INPUT_2BYTES(cinfo, length, return FALSE); |
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| 313 | |||
| 314 | INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */ |
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| 315 | |||
| 316 | TRACEMS1(cinfo, 1, JTRC_SOS, n); |
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| 317 | |||
| 318 | if (length != (n * 2 + 6) || n < 1 || n > MAX_COMPS_IN_SCAN) |
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| 319 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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| 320 | |||
| 321 | cinfo->comps_in_scan = n; |
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| 322 | |||
| 323 | /* Collect the component-spec parameters */ |
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| 324 | |||
| 325 | for (i = 0; i < n; i++) { |
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| 326 | INPUT_BYTE(cinfo, cc, return FALSE); |
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| 327 | INPUT_BYTE(cinfo, c, return FALSE); |
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| 328 | |||
| 329 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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| 330 | ci++, compptr++) { |
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| 331 | if (cc == compptr->component_id) |
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| 332 | goto id_found; |
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| 333 | } |
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| 334 | |||
| 335 | ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc); |
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| 336 | |||
| 337 | id_found: |
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| 338 | |||
| 339 | cinfo->cur_comp_info[i] = compptr; |
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| 340 | compptr->dc_tbl_no = (c >> 4) & 15; |
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| 341 | compptr->ac_tbl_no = (c ) & 15; |
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| 342 | |||
| 343 | TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc, |
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| 344 | compptr->dc_tbl_no, compptr->ac_tbl_no); |
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| 345 | } |
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| 346 | |||
| 347 | /* Collect the additional scan parameters Ss, Se, Ah/Al. */ |
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| 348 | INPUT_BYTE(cinfo, c, return FALSE); |
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| 349 | cinfo->Ss = c; |
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| 350 | INPUT_BYTE(cinfo, c, return FALSE); |
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| 351 | cinfo->Se = c; |
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| 352 | INPUT_BYTE(cinfo, c, return FALSE); |
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| 353 | cinfo->Ah = (c >> 4) & 15; |
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| 354 | cinfo->Al = (c ) & 15; |
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| 355 | |||
| 356 | TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se, |
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| 357 | cinfo->Ah, cinfo->Al); |
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| 358 | |||
| 359 | /* Prepare to scan data & restart markers */ |
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| 360 | cinfo->marker->next_restart_num = 0; |
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| 361 | |||
| 362 | /* Count another SOS marker */ |
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| 363 | cinfo->input_scan_number++; |
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| 364 | |||
| 365 | INPUT_SYNC(cinfo); |
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| 366 | return TRUE; |
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| 367 | } |
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| 368 | |||
| 369 | |||
| 370 | #ifdef D_ARITH_CODING_SUPPORTED |
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| 371 | |||
| 372 | LOCAL(boolean) |
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| 373 | get_dac (j_decompress_ptr cinfo) |
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| 374 | /* Process a DAC marker */ |
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| 375 | { |
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| 376 | INT32 length; |
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| 377 | int index, val; |
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| 378 | INPUT_VARS(cinfo); |
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| 379 | |||
| 380 | INPUT_2BYTES(cinfo, length, return FALSE); |
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| 381 | length -= 2; |
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| 382 | |||
| 383 | while (length > 0) { |
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| 384 | INPUT_BYTE(cinfo, index, return FALSE); |
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| 385 | INPUT_BYTE(cinfo, val, return FALSE); |
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| 386 | |||
| 387 | length -= 2; |
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| 388 | |||
| 389 | TRACEMS2(cinfo, 1, JTRC_DAC, index, val); |
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| 390 | |||
| 391 | if (index < 0 || index >= (2*NUM_ARITH_TBLS)) |
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| 392 | ERREXIT1(cinfo, JERR_DAC_INDEX, index); |
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| 393 | |||
| 394 | if (index >= NUM_ARITH_TBLS) { /* define AC table */ |
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| 395 | cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val; |
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| 396 | } else { /* define DC table */ |
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| 397 | cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F); |
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| 398 | cinfo->arith_dc_U[index] = (UINT8) (val >> 4); |
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| 399 | if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index]) |
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| 400 | ERREXIT1(cinfo, JERR_DAC_VALUE, val); |
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| 401 | } |
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| 402 | } |
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| 403 | |||
| 404 | if (length != 0) |
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| 405 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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| 406 | |||
| 407 | INPUT_SYNC(cinfo); |
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| 408 | return TRUE; |
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| 409 | } |
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| 410 | |||
| 411 | #else /* ! D_ARITH_CODING_SUPPORTED */ |
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| 412 | |||
| 413 | #define get_dac(cinfo) skip_variable(cinfo) |
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| 414 | |||
| 415 | #endif /* D_ARITH_CODING_SUPPORTED */ |
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| 416 | |||
| 417 | |||
| 418 | LOCAL(boolean) |
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| 419 | get_dht (j_decompress_ptr cinfo) |
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| 420 | /* Process a DHT marker */ |
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| 421 | { |
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| 422 | INT32 length; |
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| 423 | UINT8 bits[17]; |
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| 424 | UINT8 huffval[256]; |
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| 425 | int i, index, count; |
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| 426 | JHUFF_TBL **htblptr; |
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| 427 | INPUT_VARS(cinfo); |
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| 428 | |||
| 429 | INPUT_2BYTES(cinfo, length, return FALSE); |
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| 430 | length -= 2; |
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| 431 | |||
| 432 | while (length > 16) { |
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| 433 | INPUT_BYTE(cinfo, index, return FALSE); |
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| 434 | |||
| 435 | TRACEMS1(cinfo, 1, JTRC_DHT, index); |
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| 436 | |||
| 437 | bits[0] = 0; |
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| 438 | count = 0; |
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| 439 | for (i = 1; i <= 16; i++) { |
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| 440 | INPUT_BYTE(cinfo, bits[i], return FALSE); |
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| 441 | count += bits[i]; |
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| 442 | } |
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| 443 | |||
| 444 | length -= 1 + 16; |
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| 445 | |||
| 446 | TRACEMS8(cinfo, 2, JTRC_HUFFBITS, |
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| 447 | bits[1], bits[2], bits[3], bits[4], |
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| 448 | bits[5], bits[6], bits[7], bits[8]); |
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| 449 | TRACEMS8(cinfo, 2, JTRC_HUFFBITS, |
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| 450 | bits[9], bits[10], bits[11], bits[12], |
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| 451 | bits[13], bits[14], bits[15], bits[16]); |
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| 452 | |||
| 453 | /* Here we just do minimal validation of the counts to avoid walking |
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| 454 | * off the end of our table space. jdhuff.c will check more carefully. |
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| 455 | */ |
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| 456 | if (count > 256 || ((INT32) count) > length) |
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| 457 | ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); |
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| 458 | |||
| 459 | for (i = 0; i < count; i++) |
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| 460 | INPUT_BYTE(cinfo, huffval[i], return FALSE); |
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| 461 | |||
| 462 | length -= count; |
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| 463 | |||
| 464 | if (index & 0x10) { /* AC table definition */ |
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| 465 | index -= 0x10; |
||
| 466 | htblptr = &cinfo->ac_huff_tbl_ptrs[index]; |
||
| 467 | } else { /* DC table definition */ |
||
| 468 | htblptr = &cinfo->dc_huff_tbl_ptrs[index]; |
||
| 469 | } |
||
| 470 | |||
| 471 | if (index < 0 || index >= NUM_HUFF_TBLS) |
||
| 472 | ERREXIT1(cinfo, JERR_DHT_INDEX, index); |
||
| 473 | |||
| 474 | if (*htblptr == NULL) |
||
| 475 | *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); |
||
| 476 | |||
| 477 | MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits)); |
||
| 478 | MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval)); |
||
| 479 | } |
||
| 480 | |||
| 481 | if (length != 0) |
||
| 482 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
||
| 483 | |||
| 484 | INPUT_SYNC(cinfo); |
||
| 485 | return TRUE; |
||
| 486 | } |
||
| 487 | |||
| 488 | |||
| 489 | LOCAL(boolean) |
||
| 490 | get_dqt (j_decompress_ptr cinfo) |
||
| 491 | /* Process a DQT marker */ |
||
| 492 | { |
||
| 493 | INT32 length; |
||
| 494 | int n, i, prec; |
||
| 495 | unsigned int tmp; |
||
| 496 | JQUANT_TBL *quant_ptr; |
||
| 497 | INPUT_VARS(cinfo); |
||
| 498 | |||
| 499 | INPUT_2BYTES(cinfo, length, return FALSE); |
||
| 500 | length -= 2; |
||
| 501 | |||
| 502 | while (length > 0) { |
||
| 503 | INPUT_BYTE(cinfo, n, return FALSE); |
||
| 504 | prec = n >> 4; |
||
| 505 | n &= 0x0F; |
||
| 506 | |||
| 507 | TRACEMS2(cinfo, 1, JTRC_DQT, n, prec); |
||
| 508 | |||
| 509 | if (n >= NUM_QUANT_TBLS) |
||
| 510 | ERREXIT1(cinfo, JERR_DQT_INDEX, n); |
||
| 511 | |||
| 512 | if (cinfo->quant_tbl_ptrs[n] == NULL) |
||
| 513 | cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo); |
||
| 514 | quant_ptr = cinfo->quant_tbl_ptrs[n]; |
||
| 515 | |||
| 516 | for (i = 0; i < DCTSIZE2; i++) { |
||
| 517 | if (prec) |
||
| 518 | INPUT_2BYTES(cinfo, tmp, return FALSE); |
||
| 519 | else |
||
| 520 | INPUT_BYTE(cinfo, tmp, return FALSE); |
||
| 521 | /* We convert the zigzag-order table to natural array order. */ |
||
| 522 | quant_ptr->quantval[jpeg_natural_order[i]] = (UINT16) tmp; |
||
| 523 | } |
||
| 524 | |||
| 525 | if (cinfo->err->trace_level >= 2) { |
||
| 526 | for (i = 0; i < DCTSIZE2; i += 8) { |
||
| 527 | TRACEMS8(cinfo, 2, JTRC_QUANTVALS, |
||
| 528 | quant_ptr->quantval[i], quant_ptr->quantval[i+1], |
||
| 529 | quant_ptr->quantval[i+2], quant_ptr->quantval[i+3], |
||
| 530 | quant_ptr->quantval[i+4], quant_ptr->quantval[i+5], |
||
| 531 | quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]); |
||
| 532 | } |
||
| 533 | } |
||
| 534 | |||
| 535 | length -= DCTSIZE2+1; |
||
| 536 | if (prec) length -= DCTSIZE2; |
||
| 537 | } |
||
| 538 | |||
| 539 | if (length != 0) |
||
| 540 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
||
| 541 | |||
| 542 | INPUT_SYNC(cinfo); |
||
| 543 | return TRUE; |
||
| 544 | } |
||
| 545 | |||
| 546 | |||
| 547 | LOCAL(boolean) |
||
| 548 | get_dri (j_decompress_ptr cinfo) |
||
| 549 | /* Process a DRI marker */ |
||
| 550 | { |
||
| 551 | INT32 length; |
||
| 552 | unsigned int tmp; |
||
| 553 | INPUT_VARS(cinfo); |
||
| 554 | |||
| 555 | INPUT_2BYTES(cinfo, length, return FALSE); |
||
| 556 | |||
| 557 | if (length != 4) |
||
| 558 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
||
| 559 | |||
| 560 | INPUT_2BYTES(cinfo, tmp, return FALSE); |
||
| 561 | |||
| 562 | TRACEMS1(cinfo, 1, JTRC_DRI, tmp); |
||
| 563 | |||
| 564 | cinfo->restart_interval = tmp; |
||
| 565 | |||
| 566 | INPUT_SYNC(cinfo); |
||
| 567 | return TRUE; |
||
| 568 | } |
||
| 569 | |||
| 570 | |||
| 571 | /* |
||
| 572 | * Routines for processing APPn and COM markers. |
||
| 573 | * These are either saved in memory or discarded, per application request. |
||
| 574 | * APP0 and APP14 are specially checked to see if they are |
||
| 575 | * JFIF and Adobe markers, respectively. |
||
| 576 | */ |
||
| 577 | |||
| 578 | #define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */ |
||
| 579 | #define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */ |
||
| 580 | #define APPN_DATA_LEN 14 /* Must be the largest of the above!! */ |
||
| 581 | |||
| 582 | |||
| 583 | LOCAL(void) |
||
| 584 | examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data, |
||
| 585 | unsigned int datalen, INT32 remaining) |
||
| 586 | /* Examine first few bytes from an APP0. |
||
| 587 | * Take appropriate action if it is a JFIF marker. |
||
| 588 | * datalen is # of bytes at data[], remaining is length of rest of marker data. |
||
| 589 | */ |
||
| 590 | { |
||
| 591 | INT32 totallen = (INT32) datalen + remaining; |
||
| 592 | |||
| 593 | if (datalen >= APP0_DATA_LEN && |
||
| 594 | GETJOCTET(data[0]) == 0x4A && |
||
| 595 | GETJOCTET(data[1]) == 0x46 && |
||
| 596 | GETJOCTET(data[2]) == 0x49 && |
||
| 597 | GETJOCTET(data[3]) == 0x46 && |
||
| 598 | GETJOCTET(data[4]) == 0) { |
||
| 599 | /* Found JFIF APP0 marker: save info */ |
||
| 600 | cinfo->saw_JFIF_marker = TRUE; |
||
| 601 | cinfo->JFIF_major_version = GETJOCTET(data[5]); |
||
| 602 | cinfo->JFIF_minor_version = GETJOCTET(data[6]); |
||
| 603 | cinfo->density_unit = GETJOCTET(data[7]); |
||
| 604 | cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]); |
||
| 605 | cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]); |
||
| 606 | /* Check version. |
||
| 607 | * Major version must be 1, anything else signals an incompatible change. |
||
| 608 | * (We used to treat this as an error, but now it's a nonfatal warning, |
||
| 609 | * because some bozo at Hijaak couldn't read the spec.) |
||
| 610 | * Minor version should be 0..2, but process anyway if newer. |
||
| 611 | */ |
||
| 612 | if (cinfo->JFIF_major_version != 1) |
||
| 613 | WARNMS2(cinfo, JWRN_JFIF_MAJOR, |
||
| 614 | cinfo->JFIF_major_version, cinfo->JFIF_minor_version); |
||
| 615 | /* Generate trace messages */ |
||
| 616 | TRACEMS5(cinfo, 1, JTRC_JFIF, |
||
| 617 | cinfo->JFIF_major_version, cinfo->JFIF_minor_version, |
||
| 618 | cinfo->X_density, cinfo->Y_density, cinfo->density_unit); |
||
| 619 | /* Validate thumbnail dimensions and issue appropriate messages */ |
||
| 620 | if (GETJOCTET(data[12]) | GETJOCTET(data[13])) |
||
| 621 | TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL, |
||
| 622 | GETJOCTET(data[12]), GETJOCTET(data[13])); |
||
| 623 | totallen -= APP0_DATA_LEN; |
||
| 624 | if (totallen != |
||
| 625 | ((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3)) |
||
| 626 | TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen); |
||
| 627 | } else if (datalen >= 6 && |
||
| 628 | GETJOCTET(data[0]) == 0x4A && |
||
| 629 | GETJOCTET(data[1]) == 0x46 && |
||
| 630 | GETJOCTET(data[2]) == 0x58 && |
||
| 631 | GETJOCTET(data[3]) == 0x58 && |
||
| 632 | GETJOCTET(data[4]) == 0) { |
||
| 633 | /* Found JFIF "JFXX" extension APP0 marker */ |
||
| 634 | /* The library doesn't actually do anything with these, |
||
| 635 | * but we try to produce a helpful trace message. |
||
| 636 | */ |
||
| 637 | switch (GETJOCTET(data[5])) { |
||
| 638 | case 0x10: |
||
| 639 | TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen); |
||
| 640 | break; |
||
| 641 | case 0x11: |
||
| 642 | TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen); |
||
| 643 | break; |
||
| 644 | case 0x13: |
||
| 645 | TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen); |
||
| 646 | break; |
||
| 647 | default: |
||
| 648 | TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION, |
||
| 649 | GETJOCTET(data[5]), (int) totallen); |
||
| 650 | break; |
||
| 651 | } |
||
| 652 | } else { |
||
| 653 | /* Start of APP0 does not match "JFIF" or "JFXX", or too short */ |
||
| 654 | TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen); |
||
| 655 | } |
||
| 656 | } |
||
| 657 | |||
| 658 | |||
| 659 | LOCAL(void) |
||
| 660 | examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data, |
||
| 661 | unsigned int datalen, INT32 remaining) |
||
| 662 | /* Examine first few bytes from an APP14. |
||
| 663 | * Take appropriate action if it is an Adobe marker. |
||
| 664 | * datalen is # of bytes at data[], remaining is length of rest of marker data. |
||
| 665 | */ |
||
| 666 | { |
||
| 667 | unsigned int version, flags0, flags1, transform; |
||
| 668 | |||
| 669 | if (datalen >= APP14_DATA_LEN && |
||
| 670 | GETJOCTET(data[0]) == 0x41 && |
||
| 671 | GETJOCTET(data[1]) == 0x64 && |
||
| 672 | GETJOCTET(data[2]) == 0x6F && |
||
| 673 | GETJOCTET(data[3]) == 0x62 && |
||
| 674 | GETJOCTET(data[4]) == 0x65) { |
||
| 675 | /* Found Adobe APP14 marker */ |
||
| 676 | version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]); |
||
| 677 | flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]); |
||
| 678 | flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]); |
||
| 679 | transform = GETJOCTET(data[11]); |
||
| 680 | TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform); |
||
| 681 | cinfo->saw_Adobe_marker = TRUE; |
||
| 682 | cinfo->Adobe_transform = (UINT8) transform; |
||
| 683 | } else { |
||
| 684 | /* Start of APP14 does not match "Adobe", or too short */ |
||
| 685 | TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining)); |
||
| 686 | } |
||
| 687 | } |
||
| 688 | |||
| 689 | |||
| 690 | METHODDEF(boolean) |
||
| 691 | get_interesting_appn (j_decompress_ptr cinfo) |
||
| 692 | /* Process an APP0 or APP14 marker without saving it */ |
||
| 693 | { |
||
| 694 | INT32 length; |
||
| 695 | JOCTET b[APPN_DATA_LEN]; |
||
| 696 | unsigned int i, numtoread; |
||
| 697 | INPUT_VARS(cinfo); |
||
| 698 | |||
| 699 | INPUT_2BYTES(cinfo, length, return FALSE); |
||
| 700 | length -= 2; |
||
| 701 | |||
| 702 | /* get the interesting part of the marker data */ |
||
| 703 | if (length >= APPN_DATA_LEN) |
||
| 704 | numtoread = APPN_DATA_LEN; |
||
| 705 | else if (length > 0) |
||
| 706 | numtoread = (unsigned int) length; |
||
| 707 | else |
||
| 708 | numtoread = 0; |
||
| 709 | for (i = 0; i < numtoread; i++) |
||
| 710 | INPUT_BYTE(cinfo, b[i], return FALSE); |
||
| 711 | length -= numtoread; |
||
| 712 | |||
| 713 | /* process it */ |
||
| 714 | switch (cinfo->unread_marker) { |
||
| 715 | case M_APP0: |
||
| 716 | examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length); |
||
| 717 | break; |
||
| 718 | case M_APP14: |
||
| 719 | examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length); |
||
| 720 | break; |
||
| 721 | default: |
||
| 722 | /* can't get here unless jpeg_save_markers chooses wrong processor */ |
||
| 723 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); |
||
| 724 | break; |
||
| 725 | } |
||
| 726 | |||
| 727 | /* skip any remaining data -- could be lots */ |
||
| 728 | INPUT_SYNC(cinfo); |
||
| 729 | if (length > 0) |
||
| 730 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
||
| 731 | |||
| 732 | return TRUE; |
||
| 733 | } |
||
| 734 | |||
| 735 | |||
| 736 | #ifdef SAVE_MARKERS_SUPPORTED |
||
| 737 | |||
| 738 | METHODDEF(boolean) |
||
| 739 | save_marker (j_decompress_ptr cinfo) |
||
| 740 | /* Save an APPn or COM marker into the marker list */ |
||
| 741 | { |
||
| 742 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
||
| 743 | jpeg_saved_marker_ptr cur_marker = marker->cur_marker; |
||
| 744 | unsigned int bytes_read, data_length; |
||
| 745 | JOCTET FAR * data; |
||
| 746 | INT32 length = 0; |
||
| 747 | INPUT_VARS(cinfo); |
||
| 748 | |||
| 749 | if (cur_marker == NULL) { |
||
| 750 | /* begin reading a marker */ |
||
| 751 | INPUT_2BYTES(cinfo, length, return FALSE); |
||
| 752 | length -= 2; |
||
| 753 | if (length >= 0) { /* watch out for bogus length word */ |
||
| 754 | /* figure out how much we want to save */ |
||
| 755 | unsigned int limit; |
||
| 756 | if (cinfo->unread_marker == (int) M_COM) |
||
| 757 | limit = marker->length_limit_COM; |
||
| 758 | else |
||
| 759 | limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0]; |
||
| 760 | if ((unsigned int) length < limit) |
||
| 761 | limit = (unsigned int) length; |
||
| 762 | /* allocate and initialize the marker item */ |
||
| 763 | cur_marker = (jpeg_saved_marker_ptr) |
||
| 764 | (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, |
||
| 765 | SIZEOF(struct jpeg_marker_struct) + limit); |
||
| 766 | cur_marker->next = NULL; |
||
| 767 | cur_marker->marker = (UINT8) cinfo->unread_marker; |
||
| 768 | cur_marker->original_length = (unsigned int) length; |
||
| 769 | cur_marker->data_length = limit; |
||
| 770 | /* data area is just beyond the jpeg_marker_struct */ |
||
| 771 | data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1); |
||
| 772 | marker->cur_marker = cur_marker; |
||
| 773 | marker->bytes_read = 0; |
||
| 774 | bytes_read = 0; |
||
| 775 | data_length = limit; |
||
| 776 | } else { |
||
| 777 | /* deal with bogus length word */ |
||
| 778 | bytes_read = data_length = 0; |
||
| 779 | data = NULL; |
||
| 780 | } |
||
| 781 | } else { |
||
| 782 | /* resume reading a marker */ |
||
| 783 | bytes_read = marker->bytes_read; |
||
| 784 | data_length = cur_marker->data_length; |
||
| 785 | data = cur_marker->data + bytes_read; |
||
| 786 | } |
||
| 787 | |||
| 788 | while (bytes_read < data_length) { |
||
| 789 | INPUT_SYNC(cinfo); /* move the restart point to here */ |
||
| 790 | marker->bytes_read = bytes_read; |
||
| 791 | /* If there's not at least one byte in buffer, suspend */ |
||
| 792 | MAKE_BYTE_AVAIL(cinfo, return FALSE); |
||
| 793 | /* Copy bytes with reasonable rapidity */ |
||
| 794 | while (bytes_read < data_length && bytes_in_buffer > 0) { |
||
| 795 | *data++ = *next_input_byte++; |
||
| 796 | bytes_in_buffer--; |
||
| 797 | bytes_read++; |
||
| 798 | } |
||
| 799 | } |
||
| 800 | |||
| 801 | /* Done reading what we want to read */ |
||
| 802 | if (cur_marker != NULL) { /* will be NULL if bogus length word */ |
||
| 803 | /* Add new marker to end of list */ |
||
| 804 | if (cinfo->marker_list == NULL) { |
||
| 805 | cinfo->marker_list = cur_marker; |
||
| 806 | } else { |
||
| 807 | jpeg_saved_marker_ptr prev = cinfo->marker_list; |
||
| 808 | while (prev->next != NULL) |
||
| 809 | prev = prev->next; |
||
| 810 | prev->next = cur_marker; |
||
| 811 | } |
||
| 812 | /* Reset pointer & calc remaining data length */ |
||
| 813 | data = cur_marker->data; |
||
| 814 | length = cur_marker->original_length - data_length; |
||
| 815 | } |
||
| 816 | /* Reset to initial state for next marker */ |
||
| 817 | marker->cur_marker = NULL; |
||
| 818 | |||
| 819 | /* Process the marker if interesting; else just make a generic trace msg */ |
||
| 820 | switch (cinfo->unread_marker) { |
||
| 821 | case M_APP0: |
||
| 822 | examine_app0(cinfo, data, data_length, length); |
||
| 823 | break; |
||
| 824 | case M_APP14: |
||
| 825 | examine_app14(cinfo, data, data_length, length); |
||
| 826 | break; |
||
| 827 | default: |
||
| 828 | TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, |
||
| 829 | (int) (data_length + length)); |
||
| 830 | break; |
||
| 831 | } |
||
| 832 | |||
| 833 | /* skip any remaining data -- could be lots */ |
||
| 834 | INPUT_SYNC(cinfo); /* do before skip_input_data */ |
||
| 835 | if (length > 0) |
||
| 836 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
||
| 837 | |||
| 838 | return TRUE; |
||
| 839 | } |
||
| 840 | |||
| 841 | #endif /* SAVE_MARKERS_SUPPORTED */ |
||
| 842 | |||
| 843 | |||
| 844 | METHODDEF(boolean) |
||
| 845 | skip_variable (j_decompress_ptr cinfo) |
||
| 846 | /* Skip over an unknown or uninteresting variable-length marker */ |
||
| 847 | { |
||
| 848 | INT32 length; |
||
| 849 | INPUT_VARS(cinfo); |
||
| 850 | |||
| 851 | INPUT_2BYTES(cinfo, length, return FALSE); |
||
| 852 | length -= 2; |
||
| 853 | |||
| 854 | TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length); |
||
| 855 | |||
| 856 | INPUT_SYNC(cinfo); /* do before skip_input_data */ |
||
| 857 | if (length > 0) |
||
| 858 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
||
| 859 | |||
| 860 | return TRUE; |
||
| 861 | } |
||
| 862 | |||
| 863 | |||
| 864 | /* |
||
| 865 | * Find the next JPEG marker, save it in cinfo->unread_marker. |
||
| 866 | * Returns FALSE if had to suspend before reaching a marker; |
||
| 867 | * in that case cinfo->unread_marker is unchanged. |
||
| 868 | * |
||
| 869 | * Note that the result might not be a valid marker code, |
||
| 870 | * but it will never be 0 or FF. |
||
| 871 | */ |
||
| 872 | |||
| 873 | LOCAL(boolean) |
||
| 874 | next_marker (j_decompress_ptr cinfo) |
||
| 875 | { |
||
| 876 | int c; |
||
| 877 | INPUT_VARS(cinfo); |
||
| 878 | |||
| 879 | for (;;) { |
||
| 880 | INPUT_BYTE(cinfo, c, return FALSE); |
||
| 881 | /* Skip any non-FF bytes. |
||
| 882 | * This may look a bit inefficient, but it will not occur in a valid file. |
||
| 883 | * We sync after each discarded byte so that a suspending data source |
||
| 884 | * can discard the byte from its buffer. |
||
| 885 | */ |
||
| 886 | while (c != 0xFF) { |
||
| 887 | cinfo->marker->discarded_bytes++; |
||
| 888 | INPUT_SYNC(cinfo); |
||
| 889 | INPUT_BYTE(cinfo, c, return FALSE); |
||
| 890 | } |
||
| 891 | /* This loop swallows any duplicate FF bytes. Extra FFs are legal as |
||
| 892 | * pad bytes, so don't count them in discarded_bytes. We assume there |
||
| 893 | * will not be so many consecutive FF bytes as to overflow a suspending |
||
| 894 | * data source's input buffer. |
||
| 895 | */ |
||
| 896 | do { |
||
| 897 | INPUT_BYTE(cinfo, c, return FALSE); |
||
| 898 | } while (c == 0xFF); |
||
| 899 | if (c != 0) |
||
| 900 | break; /* found a valid marker, exit loop */ |
||
| 901 | /* Reach here if we found a stuffed-zero data sequence (FF/00). |
||
| 902 | * Discard it and loop back to try again. |
||
| 903 | */ |
||
| 904 | cinfo->marker->discarded_bytes += 2; |
||
| 905 | INPUT_SYNC(cinfo); |
||
| 906 | } |
||
| 907 | |||
| 908 | if (cinfo->marker->discarded_bytes != 0) { |
||
| 909 | WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c); |
||
| 910 | cinfo->marker->discarded_bytes = 0; |
||
| 911 | } |
||
| 912 | |||
| 913 | cinfo->unread_marker = c; |
||
| 914 | |||
| 915 | INPUT_SYNC(cinfo); |
||
| 916 | return TRUE; |
||
| 917 | } |
||
| 918 | |||
| 919 | |||
| 920 | LOCAL(boolean) |
||
| 921 | first_marker (j_decompress_ptr cinfo) |
||
| 922 | /* Like next_marker, but used to obtain the initial SOI marker. */ |
||
| 923 | /* For this marker, we do not allow preceding garbage or fill; otherwise, |
||
| 924 | * we might well scan an entire input file before realizing it ain't JPEG. |
||
| 925 | * If an application wants to process non-JFIF files, it must seek to the |
||
| 926 | * SOI before calling the JPEG library. |
||
| 927 | */ |
||
| 928 | { |
||
| 929 | int c, c2; |
||
| 930 | INPUT_VARS(cinfo); |
||
| 931 | |||
| 932 | INPUT_BYTE(cinfo, c, return FALSE); |
||
| 933 | INPUT_BYTE(cinfo, c2, return FALSE); |
||
| 934 | if (c != 0xFF || c2 != (int) M_SOI) |
||
| 935 | ERREXIT2(cinfo, JERR_NO_SOI, c, c2); |
||
| 936 | |||
| 937 | cinfo->unread_marker = c2; |
||
| 938 | |||
| 939 | INPUT_SYNC(cinfo); |
||
| 940 | return TRUE; |
||
| 941 | } |
||
| 942 | |||
| 943 | |||
| 944 | /* |
||
| 945 | * Read markers until SOS or EOI. |
||
| 946 | * |
||
| 947 | * Returns same codes as are defined for jpeg_consume_input: |
||
| 948 | * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. |
||
| 949 | */ |
||
| 950 | |||
| 951 | METHODDEF(int) |
||
| 952 | read_markers (j_decompress_ptr cinfo) |
||
| 953 | { |
||
| 954 | /* Outer loop repeats once for each marker. */ |
||
| 955 | for (;;) { |
||
| 956 | /* Collect the marker proper, unless we already did. */ |
||
| 957 | /* NB: first_marker() enforces the requirement that SOI appear first. */ |
||
| 958 | if (cinfo->unread_marker == 0) { |
||
| 959 | if (! cinfo->marker->saw_SOI) { |
||
| 960 | if (! first_marker(cinfo)) |
||
| 961 | return JPEG_SUSPENDED; |
||
| 962 | } else { |
||
| 963 | if (! next_marker(cinfo)) |
||
| 964 | return JPEG_SUSPENDED; |
||
| 965 | } |
||
| 966 | } |
||
| 967 | /* At this point cinfo->unread_marker contains the marker code and the |
||
| 968 | * input point is just past the marker proper, but before any parameters. |
||
| 969 | * A suspension will cause us to return with this state still true. |
||
| 970 | */ |
||
| 971 | switch (cinfo->unread_marker) { |
||
| 972 | case M_SOI: |
||
| 973 | if (! get_soi(cinfo)) |
||
| 974 | return JPEG_SUSPENDED; |
||
| 975 | break; |
||
| 976 | |||
| 977 | case M_SOF0: /* Baseline */ |
||
| 978 | case M_SOF1: /* Extended sequential, Huffman */ |
||
| 979 | if (! get_sof(cinfo, FALSE, FALSE)) |
||
| 980 | return JPEG_SUSPENDED; |
||
| 981 | break; |
||
| 982 | |||
| 983 | case M_SOF2: /* Progressive, Huffman */ |
||
| 984 | if (! get_sof(cinfo, TRUE, FALSE)) |
||
| 985 | return JPEG_SUSPENDED; |
||
| 986 | break; |
||
| 987 | |||
| 988 | case M_SOF9: /* Extended sequential, arithmetic */ |
||
| 989 | if (! get_sof(cinfo, FALSE, TRUE)) |
||
| 990 | return JPEG_SUSPENDED; |
||
| 991 | break; |
||
| 992 | |||
| 993 | case M_SOF10: /* Progressive, arithmetic */ |
||
| 994 | if (! get_sof(cinfo, TRUE, TRUE)) |
||
| 995 | return JPEG_SUSPENDED; |
||
| 996 | break; |
||
| 997 | |||
| 998 | /* Currently unsupported SOFn types */ |
||
| 999 | case M_SOF3: /* Lossless, Huffman */ |
||
| 1000 | case M_SOF5: /* Differential sequential, Huffman */ |
||
| 1001 | case M_SOF6: /* Differential progressive, Huffman */ |
||
| 1002 | case M_SOF7: /* Differential lossless, Huffman */ |
||
| 1003 | case M_JPG: /* Reserved for JPEG extensions */ |
||
| 1004 | case M_SOF11: /* Lossless, arithmetic */ |
||
| 1005 | case M_SOF13: /* Differential sequential, arithmetic */ |
||
| 1006 | case M_SOF14: /* Differential progressive, arithmetic */ |
||
| 1007 | case M_SOF15: /* Differential lossless, arithmetic */ |
||
| 1008 | ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker); |
||
| 1009 | break; |
||
| 1010 | |||
| 1011 | case M_SOS: |
||
| 1012 | if (! get_sos(cinfo)) |
||
| 1013 | return JPEG_SUSPENDED; |
||
| 1014 | cinfo->unread_marker = 0; /* processed the marker */ |
||
| 1015 | return JPEG_REACHED_SOS; |
||
| 1016 | |||
| 1017 | case M_EOI: |
||
| 1018 | TRACEMS(cinfo, 1, JTRC_EOI); |
||
| 1019 | cinfo->unread_marker = 0; /* processed the marker */ |
||
| 1020 | return JPEG_REACHED_EOI; |
||
| 1021 | |||
| 1022 | case M_DAC: |
||
| 1023 | if (! get_dac(cinfo)) |
||
| 1024 | return JPEG_SUSPENDED; |
||
| 1025 | break; |
||
| 1026 | |||
| 1027 | case M_DHT: |
||
| 1028 | if (! get_dht(cinfo)) |
||
| 1029 | return JPEG_SUSPENDED; |
||
| 1030 | break; |
||
| 1031 | |||
| 1032 | case M_DQT: |
||
| 1033 | if (! get_dqt(cinfo)) |
||
| 1034 | return JPEG_SUSPENDED; |
||
| 1035 | break; |
||
| 1036 | |||
| 1037 | case M_DRI: |
||
| 1038 | if (! get_dri(cinfo)) |
||
| 1039 | return JPEG_SUSPENDED; |
||
| 1040 | break; |
||
| 1041 | |||
| 1042 | case M_APP0: |
||
| 1043 | case M_APP1: |
||
| 1044 | case M_APP2: |
||
| 1045 | case M_APP3: |
||
| 1046 | case M_APP4: |
||
| 1047 | case M_APP5: |
||
| 1048 | case M_APP6: |
||
| 1049 | case M_APP7: |
||
| 1050 | case M_APP8: |
||
| 1051 | case M_APP9: |
||
| 1052 | case M_APP10: |
||
| 1053 | case M_APP11: |
||
| 1054 | case M_APP12: |
||
| 1055 | case M_APP13: |
||
| 1056 | case M_APP14: |
||
| 1057 | case M_APP15: |
||
| 1058 | if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[ |
||
| 1059 | cinfo->unread_marker - (int) M_APP0]) (cinfo)) |
||
| 1060 | return JPEG_SUSPENDED; |
||
| 1061 | break; |
||
| 1062 | |||
| 1063 | case M_COM: |
||
| 1064 | if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo)) |
||
| 1065 | return JPEG_SUSPENDED; |
||
| 1066 | break; |
||
| 1067 | |||
| 1068 | case M_RST0: /* these are all parameterless */ |
||
| 1069 | case M_RST1: |
||
| 1070 | case M_RST2: |
||
| 1071 | case M_RST3: |
||
| 1072 | case M_RST4: |
||
| 1073 | case M_RST5: |
||
| 1074 | case M_RST6: |
||
| 1075 | case M_RST7: |
||
| 1076 | case M_TEM: |
||
| 1077 | TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker); |
||
| 1078 | break; |
||
| 1079 | |||
| 1080 | case M_DNL: /* Ignore DNL ... perhaps the wrong thing */ |
||
| 1081 | if (! skip_variable(cinfo)) |
||
| 1082 | return JPEG_SUSPENDED; |
||
| 1083 | break; |
||
| 1084 | |||
| 1085 | default: /* must be DHP, EXP, JPGn, or RESn */ |
||
| 1086 | /* For now, we treat the reserved markers as fatal errors since they are |
||
| 1087 | * likely to be used to signal incompatible JPEG Part 3 extensions. |
||
| 1088 | * Once the JPEG 3 version-number marker is well defined, this code |
||
| 1089 | * ought to change! |
||
| 1090 | */ |
||
| 1091 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); |
||
| 1092 | break; |
||
| 1093 | } |
||
| 1094 | /* Successfully processed marker, so reset state variable */ |
||
| 1095 | cinfo->unread_marker = 0; |
||
| 1096 | } /* end loop */ |
||
| 1097 | } |
||
| 1098 | |||
| 1099 | |||
| 1100 | /* |
||
| 1101 | * Read a restart marker, which is expected to appear next in the datastream; |
||
| 1102 | * if the marker is not there, take appropriate recovery action. |
||
| 1103 | * Returns FALSE if suspension is required. |
||
| 1104 | * |
||
| 1105 | * This is called by the entropy decoder after it has read an appropriate |
||
| 1106 | * number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder |
||
| 1107 | * has already read a marker from the data source. Under normal conditions |
||
| 1108 | * cinfo->unread_marker will be reset to 0 before returning; if not reset, |
||
| 1109 | * it holds a marker which the decoder will be unable to read past. |
||
| 1110 | */ |
||
| 1111 | |||
| 1112 | METHODDEF(boolean) |
||
| 1113 | read_restart_marker (j_decompress_ptr cinfo) |
||
| 1114 | { |
||
| 1115 | /* Obtain a marker unless we already did. */ |
||
| 1116 | /* Note that next_marker will complain if it skips any data. */ |
||
| 1117 | if (cinfo->unread_marker == 0) { |
||
| 1118 | if (! next_marker(cinfo)) |
||
| 1119 | return FALSE; |
||
| 1120 | } |
||
| 1121 | |||
| 1122 | if (cinfo->unread_marker == |
||
| 1123 | ((int) M_RST0 + cinfo->marker->next_restart_num)) { |
||
| 1124 | /* Normal case --- swallow the marker and let entropy decoder continue */ |
||
| 1125 | TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num); |
||
| 1126 | cinfo->unread_marker = 0; |
||
| 1127 | } else { |
||
| 1128 | /* Uh-oh, the restart markers have been messed up. */ |
||
| 1129 | /* Let the data source manager determine how to resync. */ |
||
| 1130 | if (! (*cinfo->src->resync_to_restart) (cinfo, |
||
| 1131 | cinfo->marker->next_restart_num)) |
||
| 1132 | return FALSE; |
||
| 1133 | } |
||
| 1134 | |||
| 1135 | /* Update next-restart state */ |
||
| 1136 | cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7; |
||
| 1137 | |||
| 1138 | return TRUE; |
||
| 1139 | } |
||
| 1140 | |||
| 1141 | |||
| 1142 | /* |
||
| 1143 | * This is the default resync_to_restart method for data source managers |
||
| 1144 | * to use if they don't have any better approach. Some data source managers |
||
| 1145 | * may be able to back up, or may have additional knowledge about the data |
||
| 1146 | * which permits a more intelligent recovery strategy; such managers would |
||
| 1147 | * presumably supply their own resync method. |
||
| 1148 | * |
||
| 1149 | * read_restart_marker calls resync_to_restart if it finds a marker other than |
||
| 1150 | * the restart marker it was expecting. (This code is *not* used unless |
||
| 1151 | * a nonzero restart interval has been declared.) cinfo->unread_marker is |
||
| 1152 | * the marker code actually found (might be anything, except 0 or FF). |
||
| 1153 | * The desired restart marker number (0..7) is passed as a parameter. |
||
| 1154 | * This routine is supposed to apply whatever error recovery strategy seems |
||
| 1155 | * appropriate in order to position the input stream to the next data segment. |
||
| 1156 | * Note that cinfo->unread_marker is treated as a marker appearing before |
||
| 1157 | * the current data-source input point; usually it should be reset to zero |
||
| 1158 | * before returning. |
||
| 1159 | * Returns FALSE if suspension is required. |
||
| 1160 | * |
||
| 1161 | * This implementation is substantially constrained by wanting to treat the |
||
| 1162 | * input as a data stream; this means we can't back up. Therefore, we have |
||
| 1163 | * only the following actions to work with: |
||
| 1164 | * 1. Simply discard the marker and let the entropy decoder resume at next |
||
| 1165 | * byte of file. |
||
| 1166 | * 2. Read forward until we find another marker, discarding intervening |
||
| 1167 | * data. (In theory we could look ahead within the current bufferload, |
||
| 1168 | * without having to discard data if we don't find the desired marker. |
||
| 1169 | * This idea is not implemented here, in part because it makes behavior |
||
| 1170 | * dependent on buffer size and chance buffer-boundary positions.) |
||
| 1171 | * 3. Leave the marker unread (by failing to zero cinfo->unread_marker). |
||
| 1172 | * This will cause the entropy decoder to process an empty data segment, |
||
| 1173 | * inserting dummy zeroes, and then we will reprocess the marker. |
||
| 1174 | * |
||
| 1175 | * #2 is appropriate if we think the desired marker lies ahead, while #3 is |
||
| 1176 | * appropriate if the found marker is a future restart marker (indicating |
||
| 1177 | * that we have missed the desired restart marker, probably because it got |
||
| 1178 | * corrupted). |
||
| 1179 | * We apply #2 or #3 if the found marker is a restart marker no more than |
||
| 1180 | * two counts behind or ahead of the expected one. We also apply #2 if the |
||
| 1181 | * found marker is not a legal JPEG marker code (it's certainly bogus data). |
||
| 1182 | * If the found marker is a restart marker more than 2 counts away, we do #1 |
||
| 1183 | * (too much risk that the marker is erroneous; with luck we will be able to |
||
| 1184 | * resync at some future point). |
||
| 1185 | * For any valid non-restart JPEG marker, we apply #3. This keeps us from |
||
| 1186 | * overrunning the end of a scan. An implementation limited to single-scan |
||
| 1187 | * files might find it better to apply #2 for markers other than EOI, since |
||
| 1188 | * any other marker would have to be bogus data in that case. |
||
| 1189 | */ |
||
| 1190 | |||
| 1191 | GLOBAL(boolean) |
||
| 1192 | jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired) |
||
| 1193 | { |
||
| 1194 | int marker = cinfo->unread_marker; |
||
| 1195 | int action = 1; |
||
| 1196 | |||
| 1197 | /* Always put up a warning. */ |
||
| 1198 | WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired); |
||
| 1199 | |||
| 1200 | /* Outer loop handles repeated decision after scanning forward. */ |
||
| 1201 | for (;;) { |
||
| 1202 | if (marker < (int) M_SOF0) |
||
| 1203 | action = 2; /* invalid marker */ |
||
| 1204 | else if (marker < (int) M_RST0 || marker > (int) M_RST7) |
||
| 1205 | action = 3; /* valid non-restart marker */ |
||
| 1206 | else { |
||
| 1207 | if (marker == ((int) M_RST0 + ((desired+1) & 7)) || |
||
| 1208 | marker == ((int) M_RST0 + ((desired+2) & 7))) |
||
| 1209 | action = 3; /* one of the next two expected restarts */ |
||
| 1210 | else if (marker == ((int) M_RST0 + ((desired-1) & 7)) || |
||
| 1211 | marker == ((int) M_RST0 + ((desired-2) & 7))) |
||
| 1212 | action = 2; /* a prior restart, so advance */ |
||
| 1213 | else |
||
| 1214 | action = 1; /* desired restart or too far away */ |
||
| 1215 | } |
||
| 1216 | TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action); |
||
| 1217 | switch (action) { |
||
| 1218 | case 1: |
||
| 1219 | /* Discard marker and let entropy decoder resume processing. */ |
||
| 1220 | cinfo->unread_marker = 0; |
||
| 1221 | return TRUE; |
||
| 1222 | case 2: |
||
| 1223 | /* Scan to the next marker, and repeat the decision loop. */ |
||
| 1224 | if (! next_marker(cinfo)) |
||
| 1225 | return FALSE; |
||
| 1226 | marker = cinfo->unread_marker; |
||
| 1227 | break; |
||
| 1228 | case 3: |
||
| 1229 | /* Return without advancing past this marker. */ |
||
| 1230 | /* Entropy decoder will be forced to process an empty segment. */ |
||
| 1231 | return TRUE; |
||
| 1232 | } |
||
| 1233 | } /* end loop */ |
||
| 1234 | } |
||
| 1235 | |||
| 1236 | |||
| 1237 | /* |
||
| 1238 | * Reset marker processing state to begin a fresh datastream. |
||
| 1239 | */ |
||
| 1240 | |||
| 1241 | METHODDEF(void) |
||
| 1242 | reset_marker_reader (j_decompress_ptr cinfo) |
||
| 1243 | { |
||
| 1244 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
||
| 1245 | |||
| 1246 | cinfo->comp_info = NULL; /* until allocated by get_sof */ |
||
| 1247 | cinfo->input_scan_number = 0; /* no SOS seen yet */ |
||
| 1248 | cinfo->unread_marker = 0; /* no pending marker */ |
||
| 1249 | marker->pub.saw_SOI = FALSE; /* set internal state too */ |
||
| 1250 | marker->pub.saw_SOF = FALSE; |
||
| 1251 | marker->pub.discarded_bytes = 0; |
||
| 1252 | marker->cur_marker = NULL; |
||
| 1253 | } |
||
| 1254 | |||
| 1255 | |||
| 1256 | /* |
||
| 1257 | * Initialize the marker reader module. |
||
| 1258 | * This is called only once, when the decompression object is created. |
||
| 1259 | */ |
||
| 1260 | |||
| 1261 | GLOBAL(void) |
||
| 1262 | jinit_marker_reader (j_decompress_ptr cinfo) |
||
| 1263 | { |
||
| 1264 | my_marker_ptr marker; |
||
| 1265 | int i; |
||
| 1266 | |||
| 1267 | /* Create subobject in permanent pool */ |
||
| 1268 | marker = (my_marker_ptr) |
||
| 1269 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, |
||
| 1270 | SIZEOF(my_marker_reader)); |
||
| 1271 | cinfo->marker = (struct jpeg_marker_reader *) marker; |
||
| 1272 | /* Initialize public method pointers */ |
||
| 1273 | marker->pub.reset_marker_reader = reset_marker_reader; |
||
| 1274 | marker->pub.read_markers = read_markers; |
||
| 1275 | marker->pub.read_restart_marker = read_restart_marker; |
||
| 1276 | /* Initialize COM/APPn processing. |
||
| 1277 | * By default, we examine and then discard APP0 and APP14, |
||
| 1278 | * but simply discard COM and all other APPn. |
||
| 1279 | */ |
||
| 1280 | marker->process_COM = skip_variable; |
||
| 1281 | marker->length_limit_COM = 0; |
||
| 1282 | for (i = 0; i < 16; i++) { |
||
| 1283 | marker->process_APPn[i] = skip_variable; |
||
| 1284 | marker->length_limit_APPn[i] = 0; |
||
| 1285 | } |
||
| 1286 | marker->process_APPn[0] = get_interesting_appn; |
||
| 1287 | marker->process_APPn[14] = get_interesting_appn; |
||
| 1288 | /* Reset marker processing state */ |
||
| 1289 | reset_marker_reader(cinfo); |
||
| 1290 | } |
||
| 1291 | |||
| 1292 | |||
| 1293 | /* |
||
| 1294 | * Control saving of COM and APPn markers into marker_list. |
||
| 1295 | */ |
||
| 1296 | |||
| 1297 | #ifdef SAVE_MARKERS_SUPPORTED |
||
| 1298 | |||
| 1299 | GLOBAL(void) |
||
| 1300 | jpeg_save_markers (j_decompress_ptr cinfo, int marker_code, |
||
| 1301 | unsigned int length_limit) |
||
| 1302 | { |
||
| 1303 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
||
| 1304 | long maxlength; |
||
| 1305 | jpeg_marker_parser_method processor; |
||
| 1306 | |||
| 1307 | /* Length limit mustn't be larger than what we can allocate |
||
| 1308 | * (should only be a concern in a 16-bit environment). |
||
| 1309 | */ |
||
| 1310 | maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct); |
||
| 1311 | if (((long) length_limit) > maxlength) |
||
| 1312 | length_limit = (unsigned int) maxlength; |
||
| 1313 | |||
| 1314 | /* Choose processor routine to use. |
||
| 1315 | * APP0/APP14 have special requirements. |
||
| 1316 | */ |
||
| 1317 | if (length_limit) { |
||
| 1318 | processor = save_marker; |
||
| 1319 | /* If saving APP0/APP14, save at least enough for our internal use. */ |
||
| 1320 | if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN) |
||
| 1321 | length_limit = APP0_DATA_LEN; |
||
| 1322 | else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN) |
||
| 1323 | length_limit = APP14_DATA_LEN; |
||
| 1324 | } else { |
||
| 1325 | processor = skip_variable; |
||
| 1326 | /* If discarding APP0/APP14, use our regular on-the-fly processor. */ |
||
| 1327 | if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14) |
||
| 1328 | processor = get_interesting_appn; |
||
| 1329 | } |
||
| 1330 | |||
| 1331 | if (marker_code == (int) M_COM) { |
||
| 1332 | marker->process_COM = processor; |
||
| 1333 | marker->length_limit_COM = length_limit; |
||
| 1334 | } else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) { |
||
| 1335 | marker->process_APPn[marker_code - (int) M_APP0] = processor; |
||
| 1336 | marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit; |
||
| 1337 | } else |
||
| 1338 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); |
||
| 1339 | } |
||
| 1340 | |||
| 1341 | #endif /* SAVE_MARKERS_SUPPORTED */ |
||
| 1342 | |||
| 1343 | |||
| 1344 | /* |
||
| 1345 | * Install a special processing method for COM or APPn markers. |
||
| 1346 | */ |
||
| 1347 | |||
| 1348 | GLOBAL(void) |
||
| 1349 | jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code, |
||
| 1350 | jpeg_marker_parser_method routine) |
||
| 1351 | { |
||
| 1352 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
||
| 1353 | |||
| 1354 | if (marker_code == (int) M_COM) |
||
| 1355 | marker->process_COM = routine; |
||
| 1356 | else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) |
||
| 1357 | marker->process_APPn[marker_code - (int) M_APP0] = routine; |
||
| 1358 | else |
||
| 1359 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); |
||
| 1360 | } |