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📄 sp5xdec.c

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/* * Sunplus JPEG decoder (SP5X) * Copyright (c) 2003 Alex Beregszaszi * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA *//** * @file sp5xdec.c * Sunplus JPEG decoder (SP5X). */#include "avcodec.h"#include "mjpeg.h"#include "mjpegdec.h"#include "sp5x.h"#undef memcpy#define memcpy uc_memcpystatic int sp5x_decode_frame(AVCodecContext *avctx,                              void *data, int *data_size,                              uint8_t *buf, int buf_size){#if 0    MJpegDecodeContext *s = avctx->priv_data;#endif    const int qscale = 5;    uint8_t *buf_ptr, *buf_end, *recoded;    int i = 0, j = 0;    if (!avctx->width || !avctx->height)        return -1;    buf_ptr = buf;    buf_end = buf + buf_size;#if 1    recoded = av_mallocz(buf_size + 1024);    if (!recoded)        return -1;    /* SOI */    recoded[j++] = 0xFF;    recoded[j++] = 0xD8;    memcpy(recoded+j, &sp5x_data_dqt[0], sizeof(sp5x_data_dqt));    memcpy(recoded+j+5, &sp5x_quant_table[qscale * 2], 64);    memcpy(recoded+j+70, &sp5x_quant_table[(qscale * 2) + 1], 64);    j += sizeof(sp5x_data_dqt);    memcpy(recoded+j, &sp5x_data_dht[0], sizeof(sp5x_data_dht));    j += sizeof(sp5x_data_dht);    memcpy(recoded+j, &sp5x_data_sof[0], sizeof(sp5x_data_sof));    AV_WB16(recoded+j+5, avctx->coded_height);    AV_WB16(recoded+j+7, avctx->coded_width);    j += sizeof(sp5x_data_sof);    memcpy(recoded+j, &sp5x_data_sos[0], sizeof(sp5x_data_sos));    j += sizeof(sp5x_data_sos);    if(avctx->codec_id==CODEC_ID_AMV)        for (i = 2; i < buf_size-2 && j < buf_size+1024-2; i++)            recoded[j++] = buf[i];    else    for (i = 14; i < buf_size && j < buf_size+1024-2; i++)    {        recoded[j++] = buf[i];        if (buf[i] == 0xff)            recoded[j++] = 0;    }    /* EOI */    recoded[j++] = 0xFF;    recoded[j++] = 0xD9;    i = ff_mjpeg_decode_frame(avctx, data, data_size, recoded, j);    av_free(recoded);#else    /* SOF */    s->bits = 8;    s->width  = avctx->coded_width;    s->height = avctx->coded_height;    s->nb_components = 3;    s->component_id[0] = 0;    s->h_count[0] = 2;    s->v_count[0] = 2;    s->quant_index[0] = 0;    s->component_id[1] = 1;    s->h_count[1] = 1;    s->v_count[1] = 1;    s->quant_index[1] = 1;    s->component_id[2] = 2;    s->h_count[2] = 1;    s->v_count[2] = 1;    s->quant_index[2] = 1;    s->h_max = 2;    s->v_max = 2;    s->qscale_table = av_mallocz((s->width+15)/16);    avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV420P : PIX_FMT_YUVJ420;    s->interlaced = 0;    s->picture.reference = 0;    if (avctx->get_buffer(avctx, &s->picture) < 0)    {        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");        return -1;    }    s->picture.pict_type = I_TYPE;    s->picture.key_frame = 1;    for (i = 0; i < 3; i++)        s->linesize[i] = s->picture.linesize[i] << s->interlaced;    /* DQT */    for (i = 0; i < 64; i++)    {        j = s->scantable.permutated[i];        s->quant_matrixes[0][j] = sp5x_quant_table[(qscale * 2) + i];    }    s->qscale[0] = FFMAX(        s->quant_matrixes[0][s->scantable.permutated[1]],        s->quant_matrixes[0][s->scantable.permutated[8]]) >> 1;    for (i = 0; i < 64; i++)    {        j = s->scantable.permutated[i];        s->quant_matrixes[1][j] = sp5x_quant_table[(qscale * 2) + 1 + i];    }    s->qscale[1] = FFMAX(        s->quant_matrixes[1][s->scantable.permutated[1]],        s->quant_matrixes[1][s->scantable.permutated[8]]) >> 1;    /* DHT */    /* SOS */    s->comp_index[0] = 0;    s->nb_blocks[0] = s->h_count[0] * s->v_count[0];    s->h_scount[0] = s->h_count[0];    s->v_scount[0] = s->v_count[0];    s->dc_index[0] = 0;    s->ac_index[0] = 0;    s->comp_index[1] = 1;    s->nb_blocks[1] = s->h_count[1] * s->v_count[1];    s->h_scount[1] = s->h_count[1];    s->v_scount[1] = s->v_count[1];    s->dc_index[1] = 1;    s->ac_index[1] = 1;    s->comp_index[2] = 2;    s->nb_blocks[2] = s->h_count[2] * s->v_count[2];    s->h_scount[2] = s->h_count[2];    s->v_scount[2] = s->v_count[2];    s->dc_index[2] = 1;    s->ac_index[2] = 1;    for (i = 0; i < 3; i++)        s->last_dc[i] = 1024;    s->mb_width = (s->width * s->h_max * 8 -1) / (s->h_max * 8);    s->mb_height = (s->height * s->v_max * 8 -1) / (s->v_max * 8);    init_get_bits(&s->gb, buf+14, (buf_size-14)*8);    return mjpeg_decode_scan(s);#endif    return i;}AVCodec sp5x_decoder = {    "sp5x",    CODEC_TYPE_VIDEO,    CODEC_ID_SP5X,    sizeof(MJpegDecodeContext),    ff_mjpeg_decode_init,    NULL,    ff_mjpeg_decode_end,    sp5x_decode_frame,    CODEC_CAP_DR1,    NULL};AVCodec amv_decoder = {    "amv",    CODEC_TYPE_VIDEO,    CODEC_ID_AMV,    sizeof(MJpegDecodeContext),    ff_mjpeg_decode_init,    NULL,    ff_mjpeg_decode_end,    sp5x_decode_frame,    CODEC_CAP_DR1};

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