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FFmpeg/libavcodec/utils.c
Fabrice Bellard 4e66ab3bab added MJPEG decoder + comments
Originally committed as revision 35 to svn://svn.ffmpeg.org/ffmpeg/trunk
2001-08-06 00:47:03 +00:00

320 lines
7.9 KiB
C

/*
* utils for libavcodec
* Copyright (c) 2001 Gerard Lantau.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "common.h"
#include "dsputil.h"
#include "avcodec.h"
/* memory alloc */
void *av_mallocz(int size)
{
void *ptr;
ptr = malloc(size);
if (!ptr)
return NULL;
memset(ptr, 0, size);
return ptr;
}
/* encoder management */
AVCodec *first_avcodec;
void register_avcodec(AVCodec *format)
{
AVCodec **p;
p = &first_avcodec;
while (*p != NULL) p = &(*p)->next;
*p = format;
format->next = NULL;
}
int avcodec_open(AVCodecContext *avctx, AVCodec *codec)
{
int ret;
avctx->codec = codec;
avctx->frame_number = 0;
avctx->priv_data = av_mallocz(codec->priv_data_size);
if (!avctx->priv_data)
return -ENOMEM;
ret = avctx->codec->init(avctx);
if (ret < 0) {
free(avctx->priv_data);
avctx->priv_data = NULL;
return ret;
}
return 0;
}
int avcodec_encode_audio(AVCodecContext *avctx, UINT8 *buf, int buf_size,
const short *samples)
{
int ret;
ret = avctx->codec->encode(avctx, buf, buf_size, (void *)samples);
avctx->frame_number++;
return ret;
}
int avcodec_encode_video(AVCodecContext *avctx, UINT8 *buf, int buf_size,
const AVPicture *pict)
{
int ret;
ret = avctx->codec->encode(avctx, buf, buf_size, (void *)pict);
avctx->frame_number++;
return ret;
}
/* decode a frame. return -1 if error, otherwise return the number of
bytes used. If no frame could be decompressed, *got_picture_ptr is
zero. Otherwise, it is non zero */
int avcodec_decode_video(AVCodecContext *avctx, AVPicture *picture,
int *got_picture_ptr,
UINT8 *buf, int buf_size)
{
int ret;
ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
buf, buf_size);
avctx->frame_number++;
return ret;
}
/* decode an audio frame. return -1 if error, otherwise return the
*number of bytes used. If no frame could be decompressed,
*frame_size_ptr is zero. Otherwise, it is the decompressed frame
*size in BYTES. */
int avcodec_decode_audio(AVCodecContext *avctx, INT16 *samples,
int *frame_size_ptr,
UINT8 *buf, int buf_size)
{
int ret;
ret = avctx->codec->decode(avctx, samples, frame_size_ptr,
buf, buf_size);
avctx->frame_number++;
return ret;
}
int avcodec_close(AVCodecContext *avctx)
{
if (avctx->codec->close)
avctx->codec->close(avctx);
free(avctx->priv_data);
avctx->priv_data = NULL;
avctx->codec = NULL;
return 0;
}
AVCodec *avcodec_find_encoder(enum CodecID id)
{
AVCodec *p;
p = first_avcodec;
while (p) {
if (p->encode != NULL && p->id == id)
return p;
p = p->next;
}
return NULL;
}
AVCodec *avcodec_find_decoder(enum CodecID id)
{
AVCodec *p;
p = first_avcodec;
while (p) {
if (p->decode != NULL && p->id == id)
return p;
p = p->next;
}
return NULL;
}
AVCodec *avcodec_find_decoder_by_name(const char *name)
{
AVCodec *p;
p = first_avcodec;
while (p) {
if (p->decode != NULL && strcmp(name,p->name) == 0)
return p;
p = p->next;
}
return NULL;
}
AVCodec *avcodec_find(enum CodecID id)
{
AVCodec *p;
p = first_avcodec;
while (p) {
if (p->id == id)
return p;
p = p->next;
}
return NULL;
}
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
{
const char *codec_name;
AVCodec *p;
char buf1[32];
if (encode)
p = avcodec_find_encoder(enc->codec_id);
else
p = avcodec_find_decoder(enc->codec_id);
if (p) {
codec_name = p->name;
} else if (enc->codec_name[0] != '\0') {
codec_name = enc->codec_name;
} else {
/* output avi tags */
if (enc->codec_type == CODEC_TYPE_VIDEO) {
snprintf(buf1, sizeof(buf1), "%c%c%c%c",
enc->codec_tag & 0xff,
(enc->codec_tag >> 8) & 0xff,
(enc->codec_tag >> 16) & 0xff,
(enc->codec_tag >> 24) & 0xff);
} else {
snprintf(buf1, sizeof(buf1), "0x%04x", enc->codec_tag);
}
codec_name = buf1;
}
switch(enc->codec_type) {
case CODEC_TYPE_VIDEO:
snprintf(buf, buf_size,
"Video: %s%s",
codec_name, enc->flags & CODEC_FLAG_HQ ? " (hq)" : "");
if (enc->width) {
snprintf(buf + strlen(buf), buf_size - strlen(buf),
", %dx%d, %0.2f fps",
enc->width, enc->height,
(float)enc->frame_rate / FRAME_RATE_BASE);
}
break;
case CODEC_TYPE_AUDIO:
snprintf(buf, buf_size,
"Audio: %s",
codec_name);
if (enc->sample_rate) {
snprintf(buf + strlen(buf), buf_size - strlen(buf),
", %d Hz, %s",
enc->sample_rate,
enc->channels == 2 ? "stereo" : "mono");
}
break;
default:
abort();
}
if (enc->bit_rate != 0) {
snprintf(buf + strlen(buf), buf_size - strlen(buf),
", %d kb/s", enc->bit_rate / 1000);
}
}
/* must be called before any other functions */
void avcodec_init(void)
{
dsputil_init();
}
/* simple call to use all the codecs */
void avcodec_register_all(void)
{
/* encoders */
#ifdef CONFIG_ENCODERS
register_avcodec(&ac3_encoder);
register_avcodec(&mp2_encoder);
register_avcodec(&mpeg1video_encoder);
register_avcodec(&h263_encoder);
register_avcodec(&h263p_encoder);
register_avcodec(&rv10_encoder);
register_avcodec(&mjpeg_encoder);
register_avcodec(&opendivx_encoder);
register_avcodec(&msmpeg4_encoder);
#endif /* CONFIG_ENCODERS */
register_avcodec(&pcm_codec);
register_avcodec(&rawvideo_codec);
/* decoders */
#ifdef CONFIG_DECODERS
register_avcodec(&h263_decoder);
register_avcodec(&opendivx_decoder);
register_avcodec(&msmpeg4_decoder);
register_avcodec(&mpeg_decoder);
register_avcodec(&h263i_decoder);
register_avcodec(&rv10_decoder);
register_avcodec(&mjpeg_decoder);
#ifdef CONFIG_MPGLIB
register_avcodec(&mp3_decoder);
#endif
#ifdef CONFIG_AC3
register_avcodec(&ac3_decoder);
#endif
#endif /* CONFIG_DECODERS */
}
static int encode_init(AVCodecContext *s)
{
return 0;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
UINT8 *buf, int buf_size)
{
return -1;
}
static int encode_frame(AVCodecContext *avctx,
unsigned char *frame, int buf_size, void *data)
{
return -1;
}
/* dummy pcm codec */
AVCodec pcm_codec = {
"pcm",
CODEC_TYPE_AUDIO,
CODEC_ID_PCM,
0,
encode_init,
encode_frame,
NULL,
decode_frame,
};
AVCodec rawvideo_codec = {
"rawvideo",
CODEC_TYPE_VIDEO,
CODEC_ID_RAWVIDEO,
0,
encode_init,
encode_frame,
NULL,
decode_frame,
};