2
ffmpegの使い方を学び始めました。これは、すべてのチュートリアルや、利用可能な例のうち、苦難に値するものがthisです。最新のffmpeg API（2017）を使用した動画の作成
出力ビデオを作成するコードを探しています。
残念ながら、good examplesのほとんどは、ファイルを作成するのではなく、ファイルからの読み上げに焦点を当てています。コードは、2つのエラーが付属しています
g++ -I ./FFmpeg/ video.cpp -L fflibs -lavcodec -lavformat
：
Here、私は推奨されない例を発見したと私はそれがこのようになるまでそのエラーを修正するために長い時間を費やし：
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string>
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libavformat/avio.h>
#include <libavutil/opt.h>
}
#define WIDTH 800
#define HEIGHT 480
#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * FRAME_RATE))
#define FRAME_RATE 24
#define PIXEL_FORMAT AV_PIX_FMT_YUV420P
#define STREAM_DURATION 5.0 //seconds
#define BIT_RATE 400000
#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
#define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
#define AVFMT_RAWPICTURE 0x0020
using namespace std;
static int sws_flags = SWS_BICUBIC;
AVFrame *picture, *tmp_picture;
uint8_t *video_outbuf;
int frame_count, video_outbuf_size;
/****** IF LINUX ******/
inline int sprintf_s(char* buffer, size_t sizeOfBuffer, const char* format, ...)
{
va_list ap;
va_start(ap, format);
int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
va_end(ap);
return result;
}
/****** IF LINUX ******/
template<size_t sizeOfBuffer>
inline int sprintf_s(char (&buffer)[sizeOfBuffer], const char* format, ...)
{
va_list ap;
va_start(ap, format);
int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
va_end(ap);
return result;
}
static void closeVideo(AVFormatContext *oc, AVStream *st)
{
avcodec_close(st->codec);
av_free(picture->data[0]);
av_free(picture);
if (tmp_picture)
{
av_free(tmp_picture->data[0]);
av_free(tmp_picture);
}
av_free(video_outbuf);
}
static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
{
AVFrame *picture;
uint8_t *picture_buf;
int size;
picture = av_frame_alloc();
if(!picture)
return NULL;
size = avpicture_get_size(pix_fmt, width, height);
picture_buf = (uint8_t*)(av_malloc(size));
if (!picture_buf)
{
av_free(picture);
return NULL;
}
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
return picture;
}
static void openVideo(AVFormatContext *oc, AVStream *st)
{
AVCodec *codec;
AVCodecContext *c;
c = st->codec;
if(c->idct_algo == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "slow", 0);
codec = avcodec_find_encoder(c->codec_id);
if(!codec)
{
std::cout << "Codec not found." << std::endl;
std::cin.get();std::cin.get();exit(1);
}
if(codec->id == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "medium", 0);
if(avcodec_open2(c, codec, NULL) < 0)
{
std::cout << "Could not open codec." << std::endl;
std::cin.get();std::cin.get();exit(1);
}
video_outbuf = NULL;
if(!(oc->oformat->flags & AVFMT_RAWPICTURE))
{
video_outbuf_size = 200000;
video_outbuf = (uint8_t*)(av_malloc(video_outbuf_size));
}
picture = alloc_picture(c->pix_fmt, c->width, c->height);
if(!picture)
{
std::cout << "Could not allocate picture" << std::endl;
std::cin.get();exit(1);
}
tmp_picture = NULL;
if(c->pix_fmt != AV_PIX_FMT_YUV420P)
{
tmp_picture = alloc_picture(AV_PIX_FMT_YUV420P, WIDTH, HEIGHT);
if(!tmp_picture)
{
std::cout << " Could not allocate temporary picture" << std::endl;
std::cin.get();exit(1);
}
}
}
static AVStream* addVideoStream(AVFormatContext *context, enum AVCodecID codecID)
{
AVCodecContext *codec;
AVStream *stream;
stream = avformat_new_stream(context, NULL);
if(!stream)
{
std::cout << "Could not alloc stream." << std::endl;
std::cin.get();exit(1);
}
codec = stream->codec;
codec->codec_id = codecID;
codec->codec_type = AVMEDIA_TYPE_VIDEO;
// sample rate
codec->bit_rate = BIT_RATE;
// resolution must be a multiple of two
codec->width = WIDTH;
codec->height = HEIGHT;
codec->time_base.den = FRAME_RATE; // stream fps
codec->time_base.num = 1;
codec->gop_size = 12; // intra frame every twelve frames at most
codec->pix_fmt = PIXEL_FORMAT;
if(codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
codec->max_b_frames = 2; // for testing, B frames
if(codec->codec_id == AV_CODEC_ID_MPEG1VIDEO)
codec->mb_decision = 2;
if(context->oformat->flags & AVFMT_GLOBALHEADER)
codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
return stream;
}
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
{
int x, y, i;
i = frame_index;
/* Y */
for(y=0;y<height;y++) {
for(x=0;x<width;x++) {
pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;y<height/2;y++) {
for(x=0;x<width/2;x++) {
pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
}
}
}
static void write_video_frame(AVFormatContext *oc, AVStream *st)
{
int out_size, ret;
AVCodecContext *c;
static struct SwsContext *img_convert_ctx;
c = st->codec;
if(frame_count >= STREAM_NB_FRAMES)
{
}
else
{
if(c->pix_fmt != AV_PIX_FMT_YUV420P)
{
if(img_convert_ctx = NULL)
{
img_convert_ctx = sws_getContext(WIDTH, HEIGHT, AV_PIX_FMT_YUV420P, WIDTH, HEIGHT,
c->pix_fmt, sws_flags, NULL, NULL, NULL);
if(img_convert_ctx == NULL)
{
std::cout << "Cannot initialize the conversion context" << std::endl;
std::cin.get();exit(1);
}
}
fill_yuv_image(tmp_picture, frame_count, WIDTH, HEIGHT);
sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize, 0, HEIGHT,
picture->data, picture->linesize);
}
else
{
fill_yuv_image(picture, frame_count, WIDTH, HEIGHT);
}
}
if (oc->oformat->flags & AVFMT_RAWPICTURE)
{
/* raw video case. The API will change slightly in the near
futur for that */
AVPacket pkt;
av_init_packet(&pkt);
pkt.flags |= AV_PKT_FLAG_KEY;
pkt.stream_index= st->index;
pkt.data= (uint8_t *)picture;
pkt.size= sizeof(AVPicture);
ret = av_interleaved_write_frame(oc, &pkt);
}
else
{
/* encode the image */
out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
/* if zero size, it means the image was buffered */
if (out_size > 0)
{
AVPacket pkt;
av_init_packet(&pkt);
if (c->coded_frame->pts != AV_NOPTS_VALUE)
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
if(c->coded_frame->key_frame)
pkt.flags |= AV_PKT_FLAG_KEY;
pkt.stream_index= st->index;
pkt.data= video_outbuf;
pkt.size= out_size;
/* write the compressed frame in the media file */
ret = av_interleaved_write_frame(oc, &pkt);
} else {
ret = 0;
}
}
if (ret != 0) {
std::cout << "Error while writing video frames" << std::endl;
std::cin.get();exit(1);
}
frame_count++;
}
int main (int argc, char *argv[])
{
const char* filename = "test.h264";
AVOutputFormat *outputFormat;
AVFormatContext *context;
AVCodecContext *codec;
AVStream *videoStream;
double videoPTS;
// init libavcodec, register all codecs and formats
av_register_all();
// auto detect the output format from the name
outputFormat = av_guess_format(NULL, filename, NULL);
if(!outputFormat)
{
std::cout << "Cannot guess output format! Using mpeg!" << std::endl;
std::cin.get();
outputFormat = av_guess_format(NULL, "h263" , NULL);
}
if(!outputFormat)
{
std::cout << "Could not find suitable output format." << std::endl;
std::cin.get();exit(1);
}
context = avformat_alloc_context();
if(!context)
{
std::cout << "Cannot allocate avformat memory." << std::endl;
std::cin.get();exit(1);
}
context->oformat = outputFormat;
sprintf_s(context->filename, sizeof(context->filename), "%s", filename);
std::cout << "Is '" << context->filename << "' = '" << filename << "'" << std::endl;
videoStream = NULL;
outputFormat->audio_codec = AV_CODEC_ID_NONE;
videoStream = addVideoStream(context, outputFormat->video_codec);
/* still needed?
if(av_set_parameters(context, NULL) < 0)
{
std::cout << "Invalid output format parameters." << std::endl;
exit(0);
}*/
av_dump_format(context, 0, filename, 1);
if(videoStream)
openVideo(context, videoStream);
if(!outputFormat->flags & AVFMT_NOFILE)
{
if(avio_open(&context->pb, filename, AVIO_FLAG_READ_WRITE) < 0)
{
std::cout << "Could not open " << filename << std::endl;
std::cin.get();exit(1);
}
}
avformat_write_header(context, 0);
while(true)
{
if(videoStream)
videoPTS = (double) videoStream->pts.val * videoStream->time_base.num/videoStream->time_base.den;
else
videoPTS = 0.;
if((!videoStream || videoPTS >= STREAM_DURATION))
{
break;
}
write_video_frame(context, videoStream);
}
av_write_trailer(context);
if(videoStream)
closeVideo(context, videoStream);
for(int i = 0; i < context->nb_streams; i++)
{
av_freep(&context->streams[i]->codec);
av_freep(&context->streams[i]);
}
if(!(outputFormat->flags & AVFMT_NOFILE))
{
avio_close(context->pb);
}
av_free(context);
std::cin.get();
return 0;
}
コンパイル：
video.cpp:249:84: error: ‘avcodec_encode_video’ was not declared in this scope
out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
^
video.cpp: In function ‘int main(int, char**)’:
video.cpp:342:46: error: ‘AVStream {aka struct AVStream}’ has no member named ‘pts’
videoPTS = (double) videoStream->pts.val * videoStream->time_base.num/videoStream->time_base.den;
^
と非常に多くの非推奨の警告です。
video.cpp: In function ‘void closeVideo(AVFormatContext*, AVStream*)’:
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘AVFrame* alloc_picture(AVPixelFormat, int, int)’:
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:80:53: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp:87:78: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp: In function ‘void openVideo(AVFormatContext*, AVStream*)’:
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘AVStream* addVideoStream(AVFormatContext*, AVCodecID)’:
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘void write_video_frame(AVFormatContext*, AVStream*)’:
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:337:38: warning: ignoring return value of ‘int avformat_write_header(AVFormatContext*, AVDictionary**)’, declared with attribute warn_unused_result [-Wunused-result]
avformat_write_header(context, 0);
^
省略されたマクロを再定義するマクロもいくつか定義しました。最新のffmpeg APIでは、APIを置き換える必要があります。
誰かが最近のffmpeg APIに準拠するようにエラーと廃止の警告を解決するのを手伝ってもらえますか？
あなたが提供したFFmpeg doxygenリンクは、古代の0.6ブランチ用です。現在のgitマスターについては、https://www.ffmpeg.org/doxygen/trunk/output-example_8c-source.htmlを参照してください。 'doc/APIchanges'と' doc/examples'も参照してください。 – LordNeckbeard
@LordNeckbeard、このリンクに言及してくれてありがとう。今日私はそれを試しました、そして、私はすでに持っているコードよりも新しいのに、このコードはまだ廃止されているようです。 – ar2015