PeerStreamer

/*

 * MJPEG decoder

 * Copyright (c) 2000, 2001 Fabrice Bellard

 * Copyright (c) 2003 Alex Beregszaszi

 * Copyright (c) 2003-2004 Michael Niedermayer

 *

 * This file is part of Libav.

 *

 * Libav is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * Libav is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with Libav; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * MJPEG decoder.

 */

#ifndef AVCODEC_MJPEGDEC_H

#define AVCODEC_MJPEGDEC_H

#include "avcodec.h"

#include "get_bits.h"

#include "dsputil.h"

#define MAX_COMPONENTS 4

typedef struct MJpegDecodeContext {

    AVCodecContext *avctx;

    GetBitContext gb;

    int start_code; /* current start code */

    int buffer_size;

    uint8_t *buffer;

    int16_t quant_matrixes[4][64];

    VLC vlcs[3][4];

    int qscale[4];      ///< quantizer scale calculated from quant_matrixes

    int org_height;  /* size given at codec init */

    int first_picture;    /* true if decoding first picture */

    int interlaced;     /* true if interlaced */

    int bottom_field;   /* true if bottom field */

    int lossless;

    int ls;

    int progressive;

    int rgb;

    int rct;            /* standard rct */

    int pegasus_rct;    /* pegasus reversible colorspace transform */

    int bits;           /* bits per component */

    int maxval;

    int near;         ///< near lossless bound (si 0 for lossless)

    int t1,t2,t3;

    int reset;        ///< context halfing intervall ?rename

    int width, height;

    int mb_width, mb_height;

    int nb_components;

    int block_stride[MAX_COMPONENTS];

    int component_id[MAX_COMPONENTS];

    int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */

    int v_count[MAX_COMPONENTS];

    int comp_index[MAX_COMPONENTS];

    int dc_index[MAX_COMPONENTS];

    int ac_index[MAX_COMPONENTS];

    int nb_blocks[MAX_COMPONENTS];

    int h_scount[MAX_COMPONENTS];

    int v_scount[MAX_COMPONENTS];

    int h_max, v_max; /* maximum h and v counts */

    int quant_index[4];   /* quant table index for each component */

    int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */

    AVFrame picture; /* picture structure */

    int got_picture;                                ///< we found a SOF and picture is valid, too.

    int linesize[MAX_COMPONENTS];                   ///< linesize << interlaced

    int8_t *qscale_table;

    DECLARE_ALIGNED(16, DCTELEM, block)[64];

    DCTELEM (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)

    uint8_t *last_nnz[MAX_COMPONENTS];

    uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)

    ScanTable scantable;

    DSPContext dsp;

    int restart_interval;

    int restart_count;

    int buggy_avid;

    int cs_itu601;

    int interlace_polarity;

    int mjpb_skiptosod;

    int cur_scan; /* current scan, used by JPEG-LS */

    int flipped; /* true if picture is flipped */

    uint16_t (*ljpeg_buffer)[4];

    unsigned int ljpeg_buffer_size;

} MJpegDecodeContext;

int ff_mjpeg_decode_init(AVCodecContext *avctx);

int ff_mjpeg_decode_end(AVCodecContext *avctx);

int ff_mjpeg_decode_frame(AVCodecContext *avctx,

                          void *data, int *data_size,

                          AVPacket *avpkt);

int ff_mjpeg_decode_dqt(MJpegDecodeContext *s);

int ff_mjpeg_decode_dht(MJpegDecodeContext *s);

int ff_mjpeg_decode_sof(MJpegDecodeContext *s);

int ff_mjpeg_decode_sos(MJpegDecodeContext *s,

                        const uint8_t *mb_bitmask, const AVFrame *reference);

int ff_mjpeg_find_marker(MJpegDecodeContext *s,

                         const uint8_t **buf_ptr, const uint8_t *buf_end,

                         const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size);

#endif /* AVCODEC_MJPEGDEC_H */