1/* 2 * MJPEG decoder 3 * Copyright (c) 2000, 2001 Fabrice Bellard 4 * Copyright (c) 2003 Alex Beregszaszi 5 * Copyright (c) 2003-2004 Michael Niedermayer 6 * 7 * This file is part of FFmpeg. 8 * 9 * FFmpeg is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU Lesser General Public 11 * License as published by the Free Software Foundation; either 12 * version 2.1 of the License, or (at your option) any later version. 13 * 14 * FFmpeg is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with FFmpeg; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 22 */ 23 24/** 25 * @file libavcodec/mjpegdec.h 26 * MJPEG decoder. 27 */ 28 29#ifndef AVCODEC_MJPEGDEC_H 30#define AVCODEC_MJPEGDEC_H 31 32#include "avcodec.h" 33#include "bitstream.h" 34#include "dsputil.h" 35 36#define MAX_COMPONENTS 4 37 38typedef struct MJpegDecodeContext { 39 AVCodecContext *avctx; 40 GetBitContext gb; 41 42 int start_code; /* current start code */ 43 int buffer_size; 44 uint8_t *buffer; 45 46 int16_t quant_matrixes[4][64]; 47 VLC vlcs[2][4]; 48 int qscale[4]; ///< quantizer scale calculated from quant_matrixes 49 50 int org_height; /* size given at codec init */ 51 int first_picture; /* true if decoding first picture */ 52 int interlaced; /* true if interlaced */ 53 int bottom_field; /* true if bottom field */ 54 int lossless; 55 int ls; 56 int progressive; 57 int rgb; 58 int rct; /* standard rct */ 59 int pegasus_rct; /* pegasus reversible colorspace transform */ 60 int bits; /* bits per component */ 61 62 int maxval; 63 int near; ///< near lossless bound (si 0 for lossless) 64 int t1,t2,t3; 65 int reset; ///< context halfing intervall ?rename 66 67 int width, height; 68 int mb_width, mb_height; 69 int nb_components; 70 int block_stride[MAX_COMPONENTS]; 71 int component_id[MAX_COMPONENTS]; 72 int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */ 73 int v_count[MAX_COMPONENTS]; 74 int comp_index[MAX_COMPONENTS]; 75 int dc_index[MAX_COMPONENTS]; 76 int ac_index[MAX_COMPONENTS]; 77 int nb_blocks[MAX_COMPONENTS]; 78 int h_scount[MAX_COMPONENTS]; 79 int v_scount[MAX_COMPONENTS]; 80 int h_max, v_max; /* maximum h and v counts */ 81 int quant_index[4]; /* quant table index for each component */ 82 int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */ 83 AVFrame picture; /* picture structure */ 84 int linesize[MAX_COMPONENTS]; ///< linesize << interlaced 85 int8_t *qscale_table; 86 DECLARE_ALIGNED_16(DCTELEM, block[64]); 87 DCTELEM (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode) 88 uint8_t *last_nnz[MAX_COMPONENTS]; 89 uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode) 90 ScanTable scantable; 91 DSPContext dsp; 92 93 int restart_interval; 94 int restart_count; 95 96 int buggy_avid; 97 int cs_itu601; 98 int interlace_polarity; 99 100 int mjpb_skiptosod; 101 102 int cur_scan; /* current scan, used by JPEG-LS */ 103} MJpegDecodeContext; 104 105int ff_mjpeg_decode_init(AVCodecContext *avctx); 106int ff_mjpeg_decode_end(AVCodecContext *avctx); 107int ff_mjpeg_decode_frame(AVCodecContext *avctx, 108 void *data, int *data_size, 109 const uint8_t *buf, int buf_size); 110int ff_mjpeg_decode_dqt(MJpegDecodeContext *s); 111int ff_mjpeg_decode_dht(MJpegDecodeContext *s); 112int ff_mjpeg_decode_sof(MJpegDecodeContext *s); 113int ff_mjpeg_decode_sos(MJpegDecodeContext *s); 114 115#endif /* AVCODEC_MJPEGDEC_H */ 116