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Autres articles (42)
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La file d’attente de SPIPmotion
28 novembre 2010, parUne file d’attente stockée dans la base de donnée
Lors de son installation, SPIPmotion crée une nouvelle table dans la base de donnée intitulée spip_spipmotion_attentes.
Cette nouvelle table est constituée des champs suivants : id_spipmotion_attente, l’identifiant numérique unique de la tâche à traiter ; id_document, l’identifiant numérique du document original à encoder ; id_objet l’identifiant unique de l’objet auquel le document encodé devra être attaché automatiquement ; objet, le type d’objet auquel (...) -
Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page. -
Other interesting software
13 avril 2011, parWe don’t claim to be the only ones doing what we do ... and especially not to assert claims to be the best either ... What we do, we just try to do it well and getting better ...
The following list represents softwares that tend to be more or less as MediaSPIP or that MediaSPIP tries more or less to do the same, whatever ...
We don’t know them, we didn’t try them, but you can take a peek.
Videopress
Website : http://videopress.com/
License : GNU/GPL v2
Source code : (...)
Sur d’autres sites (5940)
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libavcodec avcodec_open2 returns -22
28 juillet 2012, par buchtakI am trying to learn how to encode video using libavcodec library. I use the following initialization :
avcodec_register_all();
// This works fine.
AVCodec *avcodec = avcodec_find_encoder( CODEC_ID_H264 );
AVCodecContext *avctx = avcodec_alloc_context3( avcodec );
avctx->bit_rate = 400000;
avctx->width = 640;
avctx->height = 480;
avctx->time_base.den = 15;
avctx->time_base.num = 1;
avctx->gop_size = 10;
avctx->max_b_frames = 1;
avctx->pix_fmt = PIX_FMT_YUV420P;
av_opt_set( avctx->priv_data, "preset", "slow", 0 );
// ret should be zero, but it's negative
int ret = avcodec_open2( avctx, avcodec, NULL );However,
avcodec_open2(...)always returns a negative value. Theavcodec_find_encoder(...)works fine and the returned pointer is notNULL. I use Win7 x64, 64-bit Zeranoe FFmpeg build fromhttp://ffmpeg.zeranoe.com/builds/
According to the readme the FFmpeg version is 2012-06-22 git-c17808c built with
--enable-libx264. I also triedCODEC_ID_MPEG1VIDEOand changing some of the initialization parameters, but no matter what I do, theavcodec_open2(...)always returns value-22. The decoding/encoding example provided with the Zeranoe build (it's the same one as http://ffmpeg.org/doxygen/trunk/api-example_8c-source.html) does not work either... -
Libav/ffmpeg api duplicates first frame of mp4 video and makes it second frame
22 janvier 2020, par Optic_RayI am making video mp4 file from couple of jpg image files with different sizes present as sample< number >.jpg (sample1.jpg, sample2.jpg, etc) in a folder. I modified ffmpeg muxing.c example to make it create mp4 file from these set of jpg images(for frames) and also modified it to create only video stream(no audio stream). It is able to create mp4 file with n video frames from n different jpg image files, but mp4 file it outputs when n=2 isn’t as expected. I have tried from n=1 to n=7 so far. When n=2 mp4 file is created but I could see only first jpg image as frame in the entire video. It appears as if first frame(first jpg image) is duplicated and used as second frame too, as I just can’t find image of second jpg image file when I play the video. When I make video with 2 frames from 2 different jpg files, I want first frame to be first jpg image and second frame to be second jpg image. How do I achieve that ?
ffmpeg configuration :
ffmpeg version 3.4.6-0ubuntu0.18.04.1 Copyright (c) 2000-2019 the FFmpeg developers
built with gcc 7 (Ubuntu 7.3.0-16ubuntu3)
configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
libavutil 55. 78.100 / 55. 78.100
libavcodec 57.107.100 / 57.107.100
libavformat 57. 83.100 / 57. 83.100
libavdevice 57. 10.100 / 57. 10.100
libavfilter 6.107.100 / 6.107.100
libavresample 3. 7. 0 / 3. 7. 0
libswscale 4. 8.100 / 4. 8.100
libswresample 2. 9.100 / 2. 9.100
libpostproc 54. 7.100 / 54. 7.100
Hyper fast Audio and Video encoderNumber of frames in video can be set in
#define STREAM_FRAME_RATE n//n=number of frames. Following is the entire code :#include
#include <libavutil></libavutil>avassert.h>
#include <libavutil></libavutil>channel_layout.h>
#include <libavutil></libavutil>opt.h>
#include <libavutil></libavutil>mathematics.h>
#include <libavutil></libavutil>imgutils.h>
#include <libavutil></libavutil>timestamp.h>
#include <libavformat></libavformat>avformat.h>
#include <libswscale></libswscale>swscale.h>
#include <libswresample></libswresample>swresample.h>
#define STREAM_DURATION 1
#define STREAM_FRAME_RATE 2 /* 2 image/s */
#define STREAM_PIX_FMT AV_PIX_FMT_YUV420P /* default pix_fmt */
#define SCALE_FLAGS SWS_BICUBIC
// a wrapper around a single output AVStream
typedef struct OutputStream {
AVStream *st;
AVCodecContext *enc;
/* pts of the next frame that will be generated */
int64_t next_pts;
int samples_count;
AVFrame *frame;
AVFrame *tmp_frame;
float t, tincr, tincr2;
struct SwsContext *sws_ctx;
struct SwrContext *swr_ctx;
} OutputStream;
static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
{
AVRational *time_base = &fmt_ctx->streams[pkt->stream_index]->time_base;
printf("pts:%s pts_time:%s dts:%s dts_time:%s duration:%s duration_time:%s stream_index:%d\n",
av_ts2str(pkt->pts), av_ts2timestr(pkt->pts, time_base),
av_ts2str(pkt->dts), av_ts2timestr(pkt->dts, time_base),
av_ts2str(pkt->duration), av_ts2timestr(pkt->duration, time_base),
pkt->stream_index);
}
static int write_frame(AVFormatContext *fmt_ctx, const AVRational *time_base, AVStream *st, AVPacket *pkt)
{
/* rescale output packet timestamp values from codec to stream timebase */
av_packet_rescale_ts(pkt, *time_base, st->time_base);
pkt->stream_index = st->index;
/* Write the compressed frame to the media file. */
log_packet(fmt_ctx, pkt);
return av_interleaved_write_frame(fmt_ctx, pkt);
}
/* Add an output stream. */
static void add_stream(OutputStream *ost, AVFormatContext *oc,
AVCodec **codec,
enum AVCodecID codec_id)
{
AVCodecContext *c;
int i;
/* find the encoder */
*codec = avcodec_find_encoder(codec_id);
if (!(*codec)) {
fprintf(stderr, "Could not find encoder for '%s'\n",
avcodec_get_name(codec_id));
exit(1);
}
ost->st = avformat_new_stream(oc, NULL);
if (!ost->st) {
fprintf(stderr, "Could not allocate stream\n");
exit(1);
}
ost->st->id = oc->nb_streams-1;
c = avcodec_alloc_context3(*codec);
if (!c) {
fprintf(stderr, "Could not alloc an encoding context\n");
exit(1);
}
ost->enc = c;
switch ((*codec)->type) {
case AVMEDIA_TYPE_AUDIO:
printf("######################2 audio add stream\n");
c->sample_fmt = (*codec)->sample_fmts ?
(*codec)->sample_fmts[0] : AV_SAMPLE_FMT_FLTP;
c->bit_rate = 64000;
c->sample_rate = 44100;
if ((*codec)->supported_samplerates) {
c->sample_rate = (*codec)->supported_samplerates[0];
for (i = 0; (*codec)->supported_samplerates[i]; i++) {
if ((*codec)->supported_samplerates[i] == 44100)
c->sample_rate = 44100;
}
}
c->channels = av_get_channel_layout_nb_channels(c->channel_layout);
c->channel_layout = AV_CH_LAYOUT_STEREO;
if ((*codec)->channel_layouts) {
c->channel_layout = (*codec)->channel_layouts[0];
for (i = 0; (*codec)->channel_layouts[i]; i++) {
if ((*codec)->channel_layouts[i] == AV_CH_LAYOUT_STEREO)
c->channel_layout = AV_CH_LAYOUT_STEREO;
}
}
c->channels = av_get_channel_layout_nb_channels(c->channel_layout);
ost->st->time_base = (AVRational){ 1, c->sample_rate };
break;
case AVMEDIA_TYPE_VIDEO:
printf("###################### video add stream\n");
c->codec_id = codec_id;
c->bit_rate = 400000;
/* Resolution must be a multiple of two. */
c->width = 352;
c->height = 288;
/* timebase: This is the fundamental unit of time (in seconds) in terms
* of which frame timestamps are represented. For fixed-fps content,
* timebase should be 1/framerate and timestamp increments should be
* identical to 1. */
ost->st->time_base = (AVRational){ 1, STREAM_FRAME_RATE };
c->time_base = ost->st->time_base;
c->gop_size = 12; /* emit one intra frame every twelve frames at most */
c->pix_fmt = STREAM_PIX_FMT;
if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
/* just for testing, we also add B-frames */
c->max_b_frames = 2;//2
}
if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
/* Needed to avoid using macroblocks in which some coeffs overflow.
* This does not happen with normal video, it just happens here as
* the motion of the chroma plane does not match the luma plane. */
c->mb_decision = 2;//2
}
break;
default:
break;
}
/* Some formats want stream headers to be separate. */
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
c->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
}
/**************************************************************/
/* video output */
static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
{
AVFrame *picture;
int ret;
picture = av_frame_alloc();
if (!picture)
return NULL;
picture->format = pix_fmt;
picture->width = width;
picture->height = height;
/* allocate the buffers for the frame data */
ret = av_frame_get_buffer(picture, 32);
if (ret < 0) {
fprintf(stderr, "Could not allocate frame data.\n");
exit(1);
}
return picture;
}
static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
{
int ret;
AVCodecContext *c = ost->enc;
AVDictionary *opt = NULL;
av_dict_copy(&opt, opt_arg, 0);
printf("In open video\n");
/* open the codec */
ret = avcodec_open2(c, codec, &opt);
av_dict_free(&opt);
if (ret < 0) {
fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
exit(1);
}
/* allocate and init a re-usable frame */
ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
if (!ost->frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
/* If the output format is not YUV420P, then a temporary YUV420P
* picture is needed too. It is then converted to the required
* output format. */
ost->tmp_frame = NULL;
if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
ost->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
if (!ost->tmp_frame) {
fprintf(stderr, "Could not allocate temporary picture\n");
exit(1);
}
}
/* copy the stream parameters to the muxer */
ret = avcodec_parameters_from_context(ost->st->codecpar, c);
if (ret < 0) {
fprintf(stderr, "Could not copy the stream parameters\n");
exit(1);
}
}
int open_image(const char* imageFileName,int width,int height,AVFrame *pict)
{
AVFormatContext *pFormatContext = avformat_alloc_context();
if (!pFormatContext)
{
printf("ERROR could not allocate memory for Format Context");
return 0;
}
//av_register_all();
if (avformat_open_input(&pFormatContext, imageFileName, NULL, NULL) != 0)
{
printf("ERROR could not open the file");
return 0;
}
printf("format %s, duration %ld us, bit_rate %ld", pFormatContext->iformat->name, pFormatContext->duration, pFormatContext->bit_rate);
if (avformat_find_stream_info(pFormatContext, NULL) < 0)
{
printf("ERROR could not get the stream info");
return 0;
}
AVCodecParameters *pCodecParameters = pFormatContext->streams[0]->codecpar;
printf("%d",pFormatContext->nb_streams);
AVCodec *pCodec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
if (pCodec==NULL) {
printf("ERROR unsupported codecopenimage!");
printf("---------------------------------------11");
return 0;
}
AVCodecContext *pCodecCtx =avcodec_alloc_context3(pCodec);
if (!pCodecCtx)
{
printf("failed to allocated memory for AVCodecContext");
return 0;
}
pCodecCtx->width = pCodecParameters->width;
pCodecCtx->height = pCodecParameters->height;
pCodecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
if(pCodecCtx->color_range==AVCOL_RANGE_JPEG) printf("\nAVCOL_RANGE_JPEG\n");
if (avcodec_parameters_to_context(pCodecCtx, pCodecParameters) < 0)
{
printf("failed to copy codec params to codec context");
return 0;
}
// Open codec
if(avcodec_open2(pCodecCtx, pCodec,NULL)<0)
{
printf("Could not open codec");
return 0;
}
AVFrame *pFrame = av_frame_alloc();
if (!pFrame)
{
printf("Can't allocate memory for AVFrame\n");
return 0;
}
AVPacket *packet= av_packet_alloc();
int temp=av_read_frame(pFormatContext, packet);
while (temp >= 0)
{
if(packet->stream_index != 0){
continue;}
int ret = avcodec_send_packet(pCodecCtx,packet);
if (ret < 0)
{
printf("Error while sending a packet to the decoder: %s", av_err2str(ret));
return 0;
}
ret = avcodec_receive_frame(pCodecCtx,pFrame);
if (ret = 0 || ret != AVERROR(EAGAIN) || ret != AVERROR_EOF)
{
pFrame->quality = 1;
av_packet_unref(packet);
struct SwsContext *resize;
resize = sws_getContext(pCodecParameters->width, pCodecParameters->height,
AV_PIX_FMT_YUVJ420P,
width, height,
AV_PIX_FMT_YUV420P,
SCALE_FLAGS, NULL, NULL, NULL);
sws_scale(resize,(const uint8_t * const *)pFrame->data, pFrame->linesize,
0, pCodecParameters->height, pict->data, pict->linesize);
av_packet_free(&packet);
avcodec_free_context(&pCodecCtx);
avformat_close_input(&pFormatContext);
return 1;
}
else {
printf("Error [%d] while decoding frame: %s\n", ret,
strerror(AVERROR(ret)));
return 0;
}
}
avcodec_free_context(&pCodecCtx);
avformat_close_input(&pFormatContext);
return 0;
}
static void fill_yuv_image(AVFrame *pict, int frame_index,
int width, int height)
{
int ret;
/* when we pass a frame to the encoder, it may keep a reference to it
* internally;
* make sure we do not overwrite it here*/
ret = av_frame_make_writable(pict);
if (ret < 0)
exit(1);
char filename[256];
sprintf(filename, "sample%d.jpg", frame_index+1);
if(open_image(filename,width,height,pict)!=1) exit(1);
}
static AVFrame *get_video_frame(OutputStream *ost)
{
AVCodecContext *c = ost->enc;
/* check if we want to generate more frames */
if (av_compare_ts(ost->next_pts, c->time_base,
STREAM_DURATION, (AVRational){ 1, 1 }) >= 0)
return NULL;
if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
/* as we only generate a YUV420P picture, we must convert it
* to the codec pixel format if needed */
if (!ost->sws_ctx) {
ost->sws_ctx = sws_getContext(c->width, c->height,
AV_PIX_FMT_YUV420P,
c->width, c->height,
c->pix_fmt,
SCALE_FLAGS, NULL, NULL, NULL);
if (!ost->sws_ctx) {
fprintf(stderr,
"Could not initialize the conversion context\n");
exit(1);
}
}
fill_yuv_image(ost->tmp_frame, ost->next_pts, c->width, c->height);
sws_scale(ost->sws_ctx,
(const uint8_t * const *)ost->tmp_frame->data, ost->tmp_frame->linesize,
0, c->height, ost->frame->data, ost->frame->linesize);
} else {
fill_yuv_image(ost->frame, ost->next_pts, c->width, c->height);
}
ost->frame->pts = ost->next_pts++;
return ost->frame;
}
/*
* encode one video frame and send it to the muxer
* return 1 when encoding is finished, 0 otherwise
*/
static int write_video_frame(AVFormatContext *oc, OutputStream *ost)
{
int ret;
AVCodecContext *c;
AVFrame *frame;
int got_packet = 0;
AVPacket pkt = { 0 };
c = ost->enc;
printf("In write_video_frame\n");
frame = get_video_frame(ost);
av_init_packet(&pkt);
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_packet);
if (ret < 0) {
fprintf(stderr, "Error encoding video frame: %s\n", av_err2str(ret));
exit(1);
}
if (got_packet) {
ret = write_frame(oc, &c->time_base, ost->st, &pkt);
} else {
ret = 0;
}
if (ret < 0) {
fprintf(stderr, "Error while writing video frame: %s\n", av_err2str(ret));
exit(1);
}
return (frame || got_packet) ? 0 : 1;
}
static void close_stream(AVFormatContext *oc, OutputStream *ost)
{
avcodec_free_context(&ost->enc);
av_frame_free(&ost->frame);
av_frame_free(&ost->tmp_frame);
sws_freeContext(ost->sws_ctx);
swr_free(&ost->swr_ctx);
}
/**************************************************************/
/* media file output */
int main(int argc, char **argv)
{
OutputStream video_st = { 0 };
const char *filename;
AVOutputFormat *fmt;
AVFormatContext *oc;
AVCodec *video_codec;
int ret;
int have_video = 0;
int encode_video = 0;
AVDictionary *opt = NULL;
int i;
/* Initialize libavcodec, and register all codecs and formats. */
av_register_all();
if (argc < 2) {
printf("usage: %s output_file\n"
"API example program to output a media file with libavformat.\n"
"This program generates a synthetic audio and video stream, encodes and\n"
"muxes them into a file named output_file.\n"
"The output format is automatically guessed according to the file extension.\n"
"Raw images can also be output by using '%%d' in the filename.\n"
"\n", argv[0]);
return 1;
}
filename = argv[1];
for (i = 2; i+1 < argc; i+=2) {
if (!strcmp(argv[i], "-flags") || !strcmp(argv[i], "-fflags"))
av_dict_set(&opt, argv[i]+1, argv[i+1], 0);
}
/* allocate the output media context */
avformat_alloc_output_context2(&oc, NULL, NULL, filename);
if (!oc) {
printf("Could not deduce output format from file extension: using MPEG.\n");
avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
}
if (!oc)
return 1;
fmt = oc->oformat;
/* Add the audio and video streams using the default format codecs
* and initialize the codecs. */
if (fmt->video_codec != AV_CODEC_ID_NONE) {
add_stream(&video_st, oc, &video_codec, fmt->video_codec);
have_video = 1;
encode_video = 1;
}
/* Now that all the parameters are set, we can open the audio and
* video codecs and allocate the necessary encode buffers. */
if (have_video)
open_video(oc, video_codec, &video_st, opt);
av_dump_format(oc, 0, filename, 1);
/* open the output file, if needed */
if (!(fmt->flags & AVFMT_NOFILE)) {
ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
if (ret < 0) {
fprintf(stderr, "Could not open '%s': %s\n", filename,
av_err2str(ret));
return 1;
}
}
/* Write the stream header, if any. */
ret = avformat_write_header(oc, &opt);
if (ret < 0) {
fprintf(stderr, "Error occurred when opening output file: %s\n",
av_err2str(ret));
return 1;
}
while (encode_video) {
/* select the stream to encode */
printf("######################\n");
if (encode_video &&
(av_compare_ts(video_st.next_pts, video_st.enc->time_base,STREAM_DURATION, (AVRational){ 1, 1 }) <= 0)) {
encode_video = !write_video_frame(oc, &video_st);
}
}
av_write_trailer(oc);
/* Close each codec. */
if (have_video)
close_stream(oc, &video_st);
if (!(fmt->flags & AVFMT_NOFILE))
/* Close the output file. */
avio_closep(&oc->pb);
/* free the stream */
avformat_free_context(oc);
return 0;
}``` -
Screen Recording with FFmpeg-Lib with c++
27 janvier 2020, par BaschdelI’m trying to record the whole desktop stream with FFmpeg on Windows.
I found a working example here. The Problem is that some og the functions depricated. So I tried to replace them with the updated ones.But there are some slight problems. The error "has triggered a breakpoint." occurse and also "not able to read the location."
The bigger problem is that I don’t know if this is the right way to do this..My code looks like this :
using namespace std;
/* initialize the resources*/
Recorder::Recorder()
{
av_register_all();
avcodec_register_all();
avdevice_register_all();
cout<<"\nall required functions are registered successfully";
}
/* uninitialize the resources */
Recorder::~Recorder()
{
avformat_close_input(&pAVFormatContext);
if( !pAVFormatContext )
{
cout<<"\nfile closed sucessfully";
}
else
{
cout<<"\nunable to close the file";
exit(1);
}
avformat_free_context(pAVFormatContext);
if( !pAVFormatContext )
{
cout<<"\navformat free successfully";
}
else
{
cout<<"\nunable to free avformat context";
exit(1);
}
}
/* establishing the connection between camera or screen through its respective folder */
int Recorder::openCamera()
{
value = 0;
options = NULL;
pAVFormatContext = NULL;
pAVFormatContext = avformat_alloc_context();//Allocate an AVFormatContext.
openScreen(pAVFormatContext);
/* set frame per second */
value = av_dict_set( &options,"framerate","30",0 );
if(value < 0)
{
cout<<"\nerror in setting dictionary value";
exit(1);
}
value = av_dict_set( &options, "preset", "medium", 0 );
if(value < 0)
{
cout<<"\nerror in setting preset values";
exit(1);
}
// value = avformat_find_stream_info(pAVFormatContext,NULL);
if(value < 0)
{
cout<<"\nunable to find the stream information";
exit(1);
}
VideoStreamIndx = -1;
/* find the first video stream index . Also there is an API available to do the below operations */
for(int i = 0; i < pAVFormatContext->nb_streams; i++ ) // find video stream posistion/index.
{
if( pAVFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO )
{
VideoStreamIndx = i;
break;
}
}
if( VideoStreamIndx == -1)
{
cout<<"\nunable to find the video stream index. (-1)";
exit(1);
}
// assign pAVFormatContext to VideoStreamIndx
pAVCodecContext = pAVFormatContext->streams[VideoStreamIndx]->codec;
pAVCodec = avcodec_find_decoder(pAVCodecContext->codec_id);
if( pAVCodec == NULL )
{
cout<<"\nunable to find the decoder";
exit(1);
}
value = avcodec_open2(pAVCodecContext , pAVCodec , NULL);//Initialize the AVCodecContext to use the given AVCodec.
if( value < 0 )
{
cout<<"\nunable to open the av codec";
exit(1);
}
}
/* initialize the video output file and its properties */
int Recorder::init_outputfile()
{
outAVFormatContext = NULL;
value = 0;
output_file = "output.mp4";
avformat_alloc_output_context2(&outAVFormatContext, NULL, NULL, output_file);
if (!outAVFormatContext)
{
cout<<"\nerror in allocating av format output context";
exit(1);
}
/* Returns the output format in the list of registered output formats which best matches the provided parameters, or returns NULL if there is no match. */
output_format = av_guess_format(NULL, output_file ,NULL);
if( !output_format )
{
cout<<"\nerror in guessing the video format. try with correct format";
exit(1);
}
video_st = avformat_new_stream(outAVFormatContext ,NULL);
if( !video_st )
{
cout<<"\nerror in creating a av format new stream";
exit(1);
}
if (codec_id == AV_CODEC_ID_H264)
{
av_opt_set(outAVCodecContext->priv_data, "preset", "slow", 0);
}
outAVCodec = avcodec_find_encoder(AV_CODEC_ID_MPEG4);
if (!outAVCodec)
{
cout << "\nerror in finding the av codecs. try again with correct codec";
exit(1);
}
outAVCodecContext = avcodec_alloc_context3(outAVCodec);
if( !outAVCodecContext )
{
cout<<"\nerror in allocating the codec contexts";
exit(1);
}
/* set property of the video file */
outAVCodecContext = video_st->codec;
outAVCodecContext->codec_id = AV_CODEC_ID_MPEG4;// AV_CODEC_ID_MPEG4; // AV_CODEC_ID_H264 // AV_CODEC_ID_MPEG1VIDEO
outAVCodecContext->codec_type = AVMEDIA_TYPE_VIDEO;
outAVCodecContext->pix_fmt = AV_PIX_FMT_YUV420P;
outAVCodecContext->bit_rate = 400000; // 2500000
outAVCodecContext->width = 1920;
outAVCodecContext->height = 1080;
outAVCodecContext->gop_size = 3;
outAVCodecContext->max_b_frames = 2;
outAVCodecContext->time_base.num = 1;
outAVCodecContext->time_base.den = 30; //15fps
/* Some container formats (like MP4) require global headers to be present
Mark the encoder so that it behaves accordingly. */
if ( outAVFormatContext->oformat->flags & AVFMT_GLOBALHEADER)
{
outAVCodecContext->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
}
value = avcodec_open2(outAVCodecContext, outAVCodec, NULL);
if( value < 0)
{
cout<<"\nerror in opening the avcodec";
exit(1);
}
/* create empty video file */
if ( !(outAVFormatContext->flags & AVFMT_NOFILE) )
{
if( avio_open2(&outAVFormatContext->pb , output_file , AVIO_FLAG_WRITE ,NULL, NULL) < 0 )
{
cout<<"\nerror in creating the video file";
exit(1);
}
}
if(!outAVFormatContext->nb_streams)
{
cout<<"\noutput file dose not contain any stream";
exit(1);
}
/* imp: mp4 container or some advanced container file required header information*/
value = avformat_write_header(outAVFormatContext , &options);
if(value < 0)
{
cout<<"\nerror in writing the header context";
exit(1);
}
/*
// uncomment here to view the complete video file informations
cout<<"\n\nOutput file information :\n\n";
av_dump_format(outAVFormatContext , 0 ,output_file ,1);
*/
}
int Recorder::stop() {
threading = false;
demux->join();
rescale->join();
mux->join();
return 0;
}
int Recorder::start() {
initVideoThreads();
return 0;
}
int Recorder::initVideoThreads() {
demux = new thread(&Recorder::demuxVideoStream, this, pAVCodecContext, pAVFormatContext, VideoStreamIndx);
rescale = new thread(&Recorder::rescaleVideoStream, this, pAVCodecContext, outAVCodecContext);
demux = new thread(&Recorder::encodeVideoStream, this, outAVCodecContext);
return 0;
}
void Recorder::demuxVideoStream(AVCodecContext* codecContext, AVFormatContext* formatContext, int streamIndex)
{
// init packet
AVPacket* packet = (AVPacket*)av_malloc(sizeof(AVPacket));
av_init_packet(packet);
int ctr = 0;
while (threading)
{
if (av_read_frame(formatContext, packet) < 0) {
exit(1);
}
if (packet->stream_index == streamIndex)
{
int return_value; // = 0;
ctr++;
do
{
return_value = avcodec_send_packet(codecContext, packet);
} while (return_value == AVERROR(EAGAIN) && threading);
//int i = avcodec_send_packet(codecContext, packet);
if (return_value < 0 && threading) { // call Decoder
cout << "unable to decode video";
exit(1);
}
}
}
avcodec_send_packet(codecContext, NULL); // flush decoder
// return 0;
}
void Recorder::rescaleVideoStream(AVCodecContext* inCodecContext, AVCodecContext* outCodecContext)
{
bool closing = false;
AVFrame* inFrame = av_frame_alloc();
if (!inFrame)
{
cout << "\nunable to release the avframe resources";
exit(1);
}
int nbytes = av_image_get_buffer_size(outAVCodecContext->pix_fmt, outAVCodecContext->width, outAVCodecContext->height, 32);
uint8_t* video_outbuf = (uint8_t*)av_malloc(nbytes);
if (video_outbuf == NULL)
{
cout << "\nunable to allocate memory";
exit(1);
}
AVFrame* outFrame = av_frame_alloc();//Allocate an AVFrame and set its fields to default values.
if (!outFrame)
{
cout << "\nunable to release the avframe resources for outframe";
exit(1);
}
// Setup the data pointers and linesizes based on the specified image parameters and the provided array.
int value = av_image_fill_arrays(outFrame->data, outFrame->linesize, video_outbuf, AV_PIX_FMT_YUV420P, outAVCodecContext->width, outAVCodecContext->height, 1); // returns : the size in bytes required for src
if (value < 0)
{
cout << "\nerror in filling image array";
}
int ctr = 0;
while (threading || !closing) {
int value = avcodec_receive_frame(inCodecContext, inFrame);
if (value == 0) {
ctr++;
SwsContext* swsCtx_ = sws_getContext(inCodecContext->width,
inCodecContext->height,
inCodecContext->pix_fmt,
outAVCodecContext->width,
outAVCodecContext->height,
outAVCodecContext->pix_fmt,
SWS_BICUBIC, NULL, NULL, NULL);
sws_scale(swsCtx_, inFrame->data, inFrame->linesize, 0, inCodecContext->height, outFrame->data, outFrame->linesize);
int return_value;
do
{
return_value = avcodec_send_frame(outCodecContext, outFrame);
} while (return_value == AVERROR(EAGAIN) && threading);
}
closing = (value == AVERROR_EOF);
}
avcodec_send_frame(outCodecContext, NULL);
// av_free(video_outbuf);
// return 0;
}
void Recorder::encodeVideoStream(AVCodecContext* codecContext)
{
bool closing = true;
AVPacket* packet = (AVPacket*)av_malloc(sizeof(AVPacket));
av_init_packet(packet);
int ctr = 0;
while (threading || !closing) {
packet->data = NULL; // packet data will be allocated by the encoder
packet->size = 0;
ctr++;
int value = avcodec_receive_packet(codecContext, packet);
if (value == 0) {
if (packet->pts != AV_NOPTS_VALUE)
packet->pts = av_rescale_q(packet->pts, video_st->codec->time_base, video_st->time_base);
if (packet->dts != AV_NOPTS_VALUE)
packet->dts = av_rescale_q(packet->dts, video_st->codec->time_base, video_st->time_base);
//printf("Write frame %3d (size= %2d)\n", j++, packet->size / 1000);
if (av_write_frame(outAVFormatContext, packet) != 0)
{
cout << "\nerror in writing video frame";
}
}
closing = (value == AVERROR_EOF);
}
value = av_write_trailer(outAVFormatContext);
if (value < 0)
{
cout << "\nerror in writing av trailer";
exit(1);
}
// av_free(packet);
// return 0;
}
int Recorder::openScreen(AVFormatContext* pFormatCtx) {
/*
X11 video input device.
To enable this input device during configuration you need libxcb installed on your system. It will be automatically detected during configuration.
This device allows one to capture a region of an X11 display.
refer : https://www.ffmpeg.org/ffmpeg-devices.html#x11grab
*/
/* current below is for screen recording. to connect with camera use v4l2 as a input parameter for av_find_input_format */
pAVInputFormat = av_find_input_format("gdigrab");
//value = avformat_open_input(&pAVFormatContext, ":0.0+10,250", pAVInputFormat, NULL);
value = avformat_open_input(&pAVFormatContext, "desktop", pAVInputFormat, NULL);
if (value != 0)
{
cout << "\nerror in opening input device";
exit(1);
}
return 0;
}
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