ffmpeg/libavcodec/avrndec.c

174 lines
5.4 KiB
C

/*
* AVRn decoder
* Copyright (c) 2012 Michael Niedermayer
*
* 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
*/
#include "avcodec.h"
#include "internal.h"
#include "mjpeg.h"
#include "mjpegdec.h"
#include "libavutil/imgutils.h"
typedef struct {
AVCodecContext *mjpeg_avctx;
int is_mjpeg;
int interlace;
int tff;
} AVRnContext;
static av_cold int init(AVCodecContext *avctx)
{
AVRnContext *a = avctx->priv_data;
int ret;
// Support "Resolution 1:1" for Avid AVI Codec
a->is_mjpeg = avctx->extradata_size < 31 || memcmp(&avctx->extradata[28], "1:1", 3);
if(!a->is_mjpeg && avctx->lowres) {
av_log(avctx, AV_LOG_ERROR, "lowres is not possible with rawvideo\n");
return AVERROR(EINVAL);
}
if(a->is_mjpeg) {
AVCodec *codec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
AVDictionary *thread_opt = NULL;
if (!codec) {
av_log(avctx, AV_LOG_ERROR, "MJPEG codec not found\n");
return AVERROR_DECODER_NOT_FOUND;
}
a->mjpeg_avctx = avcodec_alloc_context3(codec);
av_dict_set(&thread_opt, "threads", "1", 0); // Is this needed ?
a->mjpeg_avctx->refcounted_frames = 1;
a->mjpeg_avctx->flags = avctx->flags;
a->mjpeg_avctx->idct_algo = avctx->idct_algo;
a->mjpeg_avctx->lowres = avctx->lowres;
a->mjpeg_avctx->width = avctx->width;
a->mjpeg_avctx->height = avctx->height;
if ((ret = ff_codec_open2_recursive(a->mjpeg_avctx, codec, &thread_opt)) < 0) {
av_log(avctx, AV_LOG_ERROR, "MJPEG codec failed to open\n");
}
av_dict_free(&thread_opt);
return ret;
}
if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
return ret;
avctx->pix_fmt = AV_PIX_FMT_UYVY422;
if(avctx->extradata_size >= 9 && avctx->extradata[4]+28 < avctx->extradata_size) {
int ndx = avctx->extradata[4] + 4;
a->interlace = !memcmp(avctx->extradata + ndx, "1:1(", 4);
if(a->interlace) {
a->tff = avctx->extradata[ndx + 24] == 1;
}
}
return 0;
}
static av_cold int end(AVCodecContext *avctx)
{
AVRnContext *a = avctx->priv_data;
avcodec_close(a->mjpeg_avctx);
av_freep(&a->mjpeg_avctx);
return 0;
}
static int decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
AVRnContext *a = avctx->priv_data;
AVFrame *p = data;
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
int y, ret, true_height;
if(a->is_mjpeg) {
ret = avcodec_decode_video2(a->mjpeg_avctx, data, got_frame, avpkt);
if (ret >= 0 && *got_frame && avctx->width <= p->width && avctx->height <= p->height) {
int shift = p->height - avctx->height;
int subsample_h, subsample_v;
av_pix_fmt_get_chroma_sub_sample(p->format, &subsample_h, &subsample_v);
p->data[0] += p->linesize[0] * shift;
if (p->data[2]) {
p->data[1] += p->linesize[1] * (shift>>subsample_v);
p->data[2] += p->linesize[2] * (shift>>subsample_v);
}
p->width = avctx->width;
p->height = avctx->height;
}
avctx->pix_fmt = a->mjpeg_avctx->pix_fmt;
return ret;
}
true_height = buf_size / (2*avctx->width);
if(buf_size < 2*avctx->width * avctx->height) {
av_log(avctx, AV_LOG_ERROR, "packet too small\n");
return AVERROR_INVALIDDATA;
}
if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
return ret;
p->pict_type= AV_PICTURE_TYPE_I;
p->key_frame= 1;
if(a->interlace) {
buf += (true_height - avctx->height)*avctx->width;
for(y = 0; y < avctx->height-1; y+=2) {
memcpy(p->data[0] + (y+ a->tff)*p->linesize[0], buf , 2*avctx->width);
memcpy(p->data[0] + (y+!a->tff)*p->linesize[0], buf + avctx->width*true_height+4, 2*avctx->width);
buf += 2*avctx->width;
}
} else {
buf += (true_height - avctx->height)*avctx->width*2;
for(y = 0; y < avctx->height; y++) {
memcpy(p->data[0] + y*p->linesize[0], buf, 2*avctx->width);
buf += 2*avctx->width;
}
}
*got_frame = 1;
return buf_size;
}
AVCodec ff_avrn_decoder = {
.name = "avrn",
.long_name = NULL_IF_CONFIG_SMALL("Avid AVI Codec"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_AVRN,
.priv_data_size = sizeof(AVRnContext),
.init = init,
.close = end,
.decode = decode_frame,
.max_lowres = 3,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};