PeerStreamer

/*

 * JPEG image format

 * Copyright (c) 2003 Fabrice Bellard.

 *

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

 *

 * This library 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 this library; if not, write to the Free Software

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

 */

#include "avformat.h"

static int jpeg_probe(AVProbeData *pd)

{

    if (pd->buf_size >= 64 &&

        pd->buf[0] == 0xff && pd->buf[1] == 0xd8 && pd->buf[2] == 0xff)

        return AVPROBE_SCORE_MAX;

    else

        return 0;

}

typedef struct JpegOpaque {

    int (*alloc_cb)(void *opaque, AVImageInfo *info);

    void *opaque;

    int ret_code;

} JpegOpaque;

/* called by the codec to allocate the image */

static int jpeg_get_buffer(AVCodecContext *c, AVFrame *picture)

{

    JpegOpaque *jctx = c->opaque;

    AVImageInfo info1, *info = &info1;

    int ret, i;

    info->width = c->width;

    info->height = c->height;

    switch(c->pix_fmt) {

    case PIX_FMT_YUV420P:

        info->pix_fmt = PIX_FMT_YUVJ420P;

        break;

    case PIX_FMT_YUV422P:

        info->pix_fmt = PIX_FMT_YUVJ422P;

        break;

    case PIX_FMT_YUV444P:

        info->pix_fmt = PIX_FMT_YUVJ444P;

        break;

    default:

        return -1;

    }

    ret = jctx->alloc_cb(jctx->opaque, info);

    if (ret) {

        jctx->ret_code = ret;

        return -1;

    } else {

        for(i=0;i<3;i++) {

            picture->data[i] = info->pict.data[i];

            picture->linesize[i] = info->pict.linesize[i];

        }

        return 0;

    }

}

static void jpeg_img_copy(uint8_t *dst, int dst_wrap,

                     uint8_t *src, int src_wrap,

                     int width, int height)

{

    for(;height > 0; height--) {

        memcpy(dst, src, width);

        dst += dst_wrap;

        src += src_wrap;

    }

}

/* XXX: libavcodec is broken for truncated jpegs! */

#define IO_BUF_SIZE (1024*1024)

static int jpeg_read(ByteIOContext *f,

                     int (*alloc_cb)(void *opaque, AVImageInfo *info), void *opaque)

{

    AVCodecContext *c;

    AVFrame *picture, picture1;

    int len, size, got_picture, i;

    uint8_t *inbuf_ptr, inbuf[IO_BUF_SIZE];

    JpegOpaque jctx;

    jctx.alloc_cb = alloc_cb;

    jctx.opaque = opaque;

    jctx.ret_code = -1; /* default return code is error */

    c = avcodec_alloc_context();

    if (!c)

        return -1;

    picture= avcodec_alloc_frame();

    if (!picture) {

        av_free(c);

        return -1;

    }

    c->opaque = &jctx;

    c->get_buffer = jpeg_get_buffer;

    c->flags |= CODEC_FLAG_TRUNCATED; /* we dont send complete frames */

    if (avcodec_open(c, &mjpeg_decoder) < 0)

        goto fail1;

    for(;;) {

        size = get_buffer(f, inbuf, sizeof(inbuf));

        if (size == 0)

            break;

        inbuf_ptr = inbuf;

        while (size > 0) {

            len = avcodec_decode_video(c, &picture1, &got_picture,

                                       inbuf_ptr, size);

            if (len < 0)

                goto fail;

            if (got_picture)

                goto the_end;

            size -= len;

            inbuf_ptr += len;

        }

    }

 the_end:

    /* XXX: currently, the mjpeg decoder does not use AVFrame, so we

       must do it by hand */

    if (jpeg_get_buffer(c, picture) < 0)

        goto fail;

    for(i=0;i<3;i++) {

        int w, h;

        w = c->width;

        h = c->height;

        if (i >= 1) {

            switch(c->pix_fmt) {

            default:

            case PIX_FMT_YUV420P:

                w = (w + 1) >> 1;

                h = (h + 1) >> 1;

                break;

            case PIX_FMT_YUV422P:

                w = (w + 1) >> 1;

                break;

            case PIX_FMT_YUV444P:

                break;

            }

        }

        jpeg_img_copy(picture->data[i], picture->linesize[i],

                 picture1.data[i], picture1.linesize[i],

                 w, h);

    }

    jctx.ret_code = 0;

 fail:

    avcodec_close(c);

 fail1:

    av_free(picture);

    av_free(c);

    return jctx.ret_code;

}

#ifdef CONFIG_MUXERS

static int jpeg_write(ByteIOContext *pb, AVImageInfo *info)

{

    AVCodecContext *c;

    uint8_t *outbuf = NULL;

    int outbuf_size, ret, size, i;

    AVFrame *picture;

    ret = -1;

    c = avcodec_alloc_context();

    if (!c)

        return -1;

    picture = avcodec_alloc_frame();

    if (!picture)

        goto fail2;

    c->width = info->width;

    c->height = info->height;

    /* XXX: currently move that to the codec ? */

    switch(info->pix_fmt) {

    case PIX_FMT_YUVJ420P:

        c->pix_fmt = PIX_FMT_YUV420P;

        break;

    case PIX_FMT_YUVJ422P:

        c->pix_fmt = PIX_FMT_YUV422P;

        break;

    case PIX_FMT_YUVJ444P:

        c->pix_fmt = PIX_FMT_YUV444P;

        break;

    default:

        goto fail1;

    }

    for(i=0;i<3;i++) {

        picture->data[i] = info->pict.data[i];

        picture->linesize[i] = info->pict.linesize[i];

    }

    /* set the quality */

    picture->quality = 3; /* XXX: a parameter should be used */

    c->flags |= CODEC_FLAG_QSCALE;

    if (avcodec_open(c, &mjpeg_encoder) < 0)

        goto fail1;

    /* XXX: needs to sort out that size problem */

    outbuf_size = 1000000;

    outbuf = av_malloc(outbuf_size);

    size = avcodec_encode_video(c, outbuf, outbuf_size, picture);

    if (size < 0)

        goto fail;

    put_buffer(pb, outbuf, size);

    put_flush_packet(pb);

    ret = 0;

 fail:

    avcodec_close(c);

    av_free(outbuf);

 fail1:

    av_free(picture);

 fail2:

    av_free(c);

    return ret;

}

#endif //CONFIG_MUXERS

AVImageFormat jpeg_image_format = {

    "jpeg",

    "jpg,jpeg",

    jpeg_probe,

    jpeg_read,

    (1 << PIX_FMT_YUVJ420P) | (1 << PIX_FMT_YUVJ422P) | (1 << PIX_FMT_YUVJ444P),

#ifdef CONFIG_MUXERS

    jpeg_write,

#else

    NULL,

#endif //CONFIG_MUXERS

};