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ffmpeg / libavformat / jpeg.c @ c04c3282

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/*
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 * JPEG image format
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 * Copyright (c) 2003 Fabrice Bellard.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include "avformat.h"
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static int jpeg_probe(AVProbeData *pd)
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{
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    if (pd->buf_size >= 64 &&
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        pd->buf[0] == 0xff && pd->buf[1] == 0xd8 && pd->buf[2] == 0xff)
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        return AVPROBE_SCORE_MAX;
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    else
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        return 0;
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}
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typedef struct JpegOpaque {
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    int (*alloc_cb)(void *opaque, AVImageInfo *info);
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    void *opaque;
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    int ret_code;
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} JpegOpaque;
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/* called by the codec to allocate the image */
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static int jpeg_get_buffer(AVCodecContext *c, AVFrame *picture)
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{
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    JpegOpaque *jctx = c->opaque;
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    AVImageInfo info1, *info = &info1;
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    int ret, i;
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    info->width = c->width;
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    info->height = c->height;
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    switch(c->pix_fmt) {
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    case PIX_FMT_YUV420P:
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        info->pix_fmt = PIX_FMT_YUVJ420P;
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        break;
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    case PIX_FMT_YUV422P:
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        info->pix_fmt = PIX_FMT_YUVJ422P;
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        break;
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    case PIX_FMT_YUV444P:
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        info->pix_fmt = PIX_FMT_YUVJ444P;
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        break;
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    default:
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        return -1;
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    }
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    ret = jctx->alloc_cb(jctx->opaque, info);
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    if (ret) {
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        jctx->ret_code = ret;
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        return -1;
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    } else {
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        for(i=0;i<3;i++) {
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            picture->data[i] = info->pict.data[i];
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            picture->linesize[i] = info->pict.linesize[i];
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        }
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        return 0;
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    }
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}
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static void jpeg_img_copy(uint8_t *dst, int dst_wrap,
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                     uint8_t *src, int src_wrap,
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                     int width, int height)
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{
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    for(;height > 0; height--) {
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        memcpy(dst, src, width);
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        dst += dst_wrap;
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        src += src_wrap;
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    }
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}
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/* XXX: libavcodec is broken for truncated jpegs! */
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#define IO_BUF_SIZE (1024*1024)
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static int jpeg_read(ByteIOContext *f,
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                     int (*alloc_cb)(void *opaque, AVImageInfo *info), void *opaque)
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{
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    AVCodecContext *c;
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    AVFrame *picture, picture1;
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    int len, size, got_picture, i;
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    uint8_t *inbuf_ptr, inbuf[IO_BUF_SIZE];
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    JpegOpaque jctx;
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    jctx.alloc_cb = alloc_cb;
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    jctx.opaque = opaque;
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    jctx.ret_code = -1; /* default return code is error */
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    c = avcodec_alloc_context();
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    if (!c)
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        return -1;
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    picture= avcodec_alloc_frame();
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    if (!picture) {
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        av_free(c);
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        return -1;
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    }
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    c->opaque = &jctx;
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    c->get_buffer = jpeg_get_buffer;
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    c->flags |= CODEC_FLAG_TRUNCATED; /* we dont send complete frames */
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    if (avcodec_open(c, &mjpeg_decoder) < 0)
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        goto fail1;
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    for(;;) {
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        size = get_buffer(f, inbuf, sizeof(inbuf));
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        if (size == 0)
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            break;
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        inbuf_ptr = inbuf;
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        while (size > 0) {
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            len = avcodec_decode_video(c, &picture1, &got_picture,
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                                       inbuf_ptr, size);
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            if (len < 0)
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                goto fail;
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            if (got_picture)
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                goto the_end;
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            size -= len;
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            inbuf_ptr += len;
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        }
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    }
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 the_end:
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    /* XXX: currently, the mjpeg decoder does not use AVFrame, so we
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       must do it by hand */
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    if (jpeg_get_buffer(c, picture) < 0)
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        goto fail;
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    for(i=0;i<3;i++) {
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        int w, h;
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        w = c->width;
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        h = c->height;
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        if (i >= 1) {
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            switch(c->pix_fmt) {
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            default:
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            case PIX_FMT_YUV420P:
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                w = (w + 1) >> 1;
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                h = (h + 1) >> 1;
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                break;
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            case PIX_FMT_YUV422P:
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                w = (w + 1) >> 1;
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                break;
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            case PIX_FMT_YUV444P:
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                break;
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            }
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        }
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        jpeg_img_copy(picture->data[i], picture->linesize[i],
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                 picture1.data[i], picture1.linesize[i],
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                 w, h);
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    }
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    jctx.ret_code = 0;
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 fail:
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    avcodec_close(c);
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 fail1:
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    av_free(picture);
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    av_free(c);
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    return jctx.ret_code;
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}
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#ifdef CONFIG_MUXERS
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static int jpeg_write(ByteIOContext *pb, AVImageInfo *info)
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{
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    AVCodecContext *c;
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    uint8_t *outbuf = NULL;
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    int outbuf_size, ret, size, i;
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    AVFrame *picture;
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    ret = -1;
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    c = avcodec_alloc_context();
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    if (!c)
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        return -1;
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    picture = avcodec_alloc_frame();
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    if (!picture)
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        goto fail2;
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    c->width = info->width;
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    c->height = info->height;
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    /* XXX: currently move that to the codec ? */
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    switch(info->pix_fmt) {
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    case PIX_FMT_YUVJ420P:
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        c->pix_fmt = PIX_FMT_YUV420P;
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        break;
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    case PIX_FMT_YUVJ422P:
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        c->pix_fmt = PIX_FMT_YUV422P;
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        break;
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    case PIX_FMT_YUVJ444P:
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        c->pix_fmt = PIX_FMT_YUV444P;
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        break;
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    default:
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        goto fail1;
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    }
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    for(i=0;i<3;i++) {
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        picture->data[i] = info->pict.data[i];
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        picture->linesize[i] = info->pict.linesize[i];
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    }
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    /* set the quality */
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    picture->quality = 3; /* XXX: a parameter should be used */
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    c->flags |= CODEC_FLAG_QSCALE;
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    if (avcodec_open(c, &mjpeg_encoder) < 0)
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        goto fail1;
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    /* XXX: needs to sort out that size problem */
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    outbuf_size = 1000000;
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    outbuf = av_malloc(outbuf_size);
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    size = avcodec_encode_video(c, outbuf, outbuf_size, picture);
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    if (size < 0)
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        goto fail;
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    put_buffer(pb, outbuf, size);
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    put_flush_packet(pb);
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    ret = 0;
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 fail:
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    avcodec_close(c);
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    av_free(outbuf);
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 fail1:
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    av_free(picture);
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 fail2:
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    av_free(c);
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    return ret;
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}
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#endif //CONFIG_MUXERS
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AVImageFormat jpeg_image_format = {
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    "jpeg",
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    "jpg,jpeg",
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    jpeg_probe,
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    jpeg_read,
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    (1 << PIX_FMT_YUVJ420P) | (1 << PIX_FMT_YUVJ422P) | (1 << PIX_FMT_YUVJ444P),
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#ifdef CONFIG_MUXERS
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    jpeg_write,
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#else
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    NULL,
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#endif //CONFIG_MUXERS
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};