ffmpeg/libavformat/jpeg.c

208 lines
5.5 KiB
C

/*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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;
info->pix_fmt = c->pix_fmt;
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 img_copy(UINT8 *dst, int dst_wrap,
UINT8 *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;
}
}
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;
}
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;
c->pix_fmt = info->pix_fmt;
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;
}
AVImageFormat jpeg_image_format = {
"jpeg",
"jpg,jpeg",
jpeg_probe,
jpeg_read,
(1 << PIX_FMT_YUV420P) | (1 << PIX_FMT_YUV422P) | (1 << PIX_FMT_YUV444P),
jpeg_write,
};