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Emballe médias : à quoi cela sert ?
4 février 2011, parCe plugin vise à gérer des sites de mise en ligne de documents de tous types.
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Contribute to documentation
13 avril 2011Documentation is vital to the development of improved technical capabilities.
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Configuration spécifique pour PHP5
4 février 2011, parPHP5 est obligatoire, vous pouvez l’installer en suivant ce tutoriel spécifique.
Il est recommandé dans un premier temps de désactiver le safe_mode, cependant, s’il est correctement configuré et que les binaires nécessaires sont accessibles, MediaSPIP devrait fonctionner correctement avec le safe_mode activé.
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libavcodec : how to encode with h264 codec ,with mp4 container using controllable frame rate and bitrate(through c code)
26 mai 2016, par musimbateI am trying to record the screen of a pc and encode the recorded frames using h264 encoder
and wrap them into a mp4 container.I want to do this because this super user link http://superuser.com/questions/300897/what-is-a-codec-e-g-divx-and-how-does-it-differ-from-a-file-format-e-g-mp/300997#300997 suggests it allows good trade-off between size and quality of the output file.The application I am working on should allow users to record a few hours of video and have the minimum output file size with decent quality.
The code I have cooked up so far allows me to record and save .mpg(container) files with the mpeg1video encoder
Running :
ffmpeg -i test.mpg
on the output file gives the following output :
[mpegvideo @ 028c7400] Estimating duration from bitrate, this may be inaccurate
Input #0, mpegvideo, from 'test.mpg':
Duration: 00:00:00.29, bitrate: 104857 kb/s
Stream #0:0: Video: mpeg1video, yuv420p(tv), 1366x768 [SAR 1:1 DAR 683:384], 104857 kb/s, 25 fps, 25 tbr, 1200k tbn, 25 tbcI have these settings for my output :
const char * filename="test.mpg";
int codec_id= AV_CODEC_ID_MPEG1VIDEO;
AVCodec *codec11;
AVCodecContext *outContext= NULL;
int got_output;
FILE *f;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
/* put sample parameters */
outContext->bit_rate = 400000;
/* resolution must be a multiple of two */
outContext->width=pCodecCtx->width;
outContext->height=pCodecCtx->height;
/* frames per second */
outContext->time_base.num=1;
outContext->time_base.den=25;
/* emit one intra frame every ten frames
* check frame pict_type before passing frame
* to encoder, if frame->pict_type is AV_PICTURE_TYPE_I
* then gop_size is ignored and the output of encoder
* will always be I frame irrespective to gop_size
*/
outContext->gop_size = 10;
outContext->max_b_frames = 1;
outContext->pix_fmt = AV_PIX_FMT_YUV420P;When I change int codec_id= AV_CODEC_ID_MPEG1VIDEO to int codec_id= AV_CODEC_ID_H264 i get a file that does not play with vlc.
I have read that writing the
uint8_t endcode[] = { 0, 0, 1, 0xb7 };array at the end of your file when finished encoding makes your file a legitimate mpeg file.It is written like this :
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);in my code. Should I do the same thing when I change my encoder to AV_CODEC_ID_H264 ?
I am capturing using gdi input like this :
AVDictionary* options = NULL;
//Set some options
//grabbing frame rate
av_dict_set(&options,"framerate","30",0);
AVInputFormat *ifmt=av_find_input_format("gdigrab");
if(avformat_open_input(&pFormatCtx,"desktop",ifmt,&options)!=0){
printf("Couldn't open input stream.\n");
return -1;
}I want to be able to modify my grabbing rate to optimize for the outptut file size
but When I change it to 20 for example I get a video that plays so fast.How do
I get a video that plays with normal speed with frames captured at 20 fps or any
lower frame rate value ?While recording I get the following output on the standard error output :
[gdigrab @ 00cdb8e0] Capturing whole desktop as 1366x768x32 at (0,0)
Input #0, gdigrab, from '(null)':
Duration: N/A, start: 1420718663.655713, bitrate: 1006131 kb/s
Stream #0:0: Video: bmp, bgra, 1366x768, 1006131 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
[swscaler @ 00d24120] Warning: data is not aligned! This can lead to a speedloss
[mpeg1video @ 00cdd160] AVFrame.format is not set
[mpeg1video @ 00cdd160] AVFrame.width or height is not set
[mpeg1video @ 00cdd160] AVFrame.format is not set
[mpeg1video @ 00cdd160] AVFrame.width or height is not set
[mpeg1video @ 00cdd160] AVFrame.format is not setHow do I get rid of this error in my code ?
In summary :
1) How do I encode h264 video wrapped into mp4 container ?2) How do I capture at lower frame rates and still play
the encoded video at normal speed ?3) How do I set the format(and which format—depends on the codec ?)
and width and height info on the frames I write ?The code I am using in its entirety is shown below
extern "C"
{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libswscale/swscale.h"
#include "libavdevice/avdevice.h"
#include <libavutil></libavutil>opt.h>
#include <libavutil></libavutil>channel_layout.h>
#include <libavutil></libavutil>common.h>
#include <libavutil></libavutil>imgutils.h>
#include <libavutil></libavutil>mathematics.h>
#include <libavutil></libavutil>samplefmt.h>
//SDL
#include "SDL.h"
#include "SDL_thread.h"
}
//Output YUV420P
#define OUTPUT_YUV420P 0
//'1' Use Dshow
//'0' Use GDIgrab
#define USE_DSHOW 0
int main(int argc, char* argv[])
{
//1.WE HAVE THE FORMAT CONTEXT
//THIS IS FROM THE DESKTOP GRAB STREAM.
AVFormatContext *pFormatCtx;
int i, videoindex;
AVCodecContext *pCodecCtx;
AVCodec *pCodec;
av_register_all();
avformat_network_init();
//ASSIGN STH TO THE FORMAT CONTEXT.
pFormatCtx = avformat_alloc_context();
//Register Device
avdevice_register_all();
//Windows
#ifdef _WIN32
#if USE_DSHOW
//Use dshow
//
//Need to Install screen-capture-recorder
//screen-capture-recorder
//Website: http://sourceforge.net/projects/screencapturer/
//
AVInputFormat *ifmt=av_find_input_format("dshow");
//if(avformat_open_input(&pFormatCtx,"video=screen-capture-recorder",ifmt,NULL)!=0){
if(avformat_open_input(&pFormatCtx,"video=UScreenCapture",ifmt,NULL)!=0){
printf("Couldn't open input stream.\n");
return -1;
}
#else
//Use gdigrab
AVDictionary* options = NULL;
//Set some options
//grabbing frame rate
av_dict_set(&options,"framerate","30",0);
//The distance from the left edge of the screen or desktop
//av_dict_set(&options,"offset_x","20",0);
//The distance from the top edge of the screen or desktop
//av_dict_set(&options,"offset_y","40",0);
//Video frame size. The default is to capture the full screen
//av_dict_set(&options,"video_size","640x480",0);
AVInputFormat *ifmt=av_find_input_format("gdigrab");
if(avformat_open_input(&pFormatCtx,"desktop",ifmt,&options)!=0){
printf("Couldn't open input stream.\n");
return -1;
}
#endif
#endif//FOR THE WIN32 THING.
if(avformat_find_stream_info(pFormatCtx,NULL)<0)
{
printf("Couldn't find stream information.\n");
return -1;
}
videoindex=-1;
for(i=0; inb_streams; i++)
if(pFormatCtx->streams[i]->codec->codec_type
==AVMEDIA_TYPE_VIDEO)
{
videoindex=i;
break;
}
if(videoindex==-1)
{
printf("Didn't find a video stream.\n");
return -1;
}
pCodecCtx=pFormatCtx->streams[videoindex]->codec;
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
if(pCodec==NULL)
{
printf("Codec not found.\n");
return -1;
}
if(avcodec_open2(pCodecCtx, pCodec,NULL)<0)
{
printf("Could not open codec.\n");
return -1;
}
//THIS IS WHERE YOU CONTROL THE FORMAT(THROUGH FRAMES).
AVFrame *pFrame;
pFrame=av_frame_alloc();
int ret, got_picture;
AVPacket *packet=(AVPacket *)av_malloc(sizeof(AVPacket));
//TRY TO INIT THE PACKET HERE
av_init_packet(packet);
//Output Information-----------------------------
printf("File Information---------------------\n");
av_dump_format(pFormatCtx,0,NULL,0);
printf("-------------------------------------------------\n");
//<<--FOR WRITING MPG FILES
//<<--START:PREPARE TO WRITE YOUR MPG FILE.
const char * filename="test.mpg";
int codec_id= AV_CODEC_ID_MPEG1VIDEO;
AVCodec *codec11;
AVCodecContext *outContext= NULL;
int got_output;
FILE *f;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
printf("Encode video file %s\n", filename);
/* find the mpeg1 video encoder */
codec11 = avcodec_find_encoder((AVCodecID)codec_id);
if (!codec11) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
outContext = avcodec_alloc_context3(codec11);
if (!outContext) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
/* put sample parameters */
outContext->bit_rate = 400000;
/* resolution must be a multiple of two */
outContext->width=pCodecCtx->width;
outContext->height=pCodecCtx->height;
/* frames per second */
outContext->time_base.num=1;
outContext->time_base.den=25;
/* emit one intra frame every ten frames
* check frame pict_type before passing frame
* to encoder, if frame->pict_type is AV_PICTURE_TYPE_I
* then gop_size is ignored and the output of encoder
* will always be I frame irrespective to gop_size
*/
outContext->gop_size = 10;
outContext->max_b_frames = 1;
outContext->pix_fmt = AV_PIX_FMT_YUV420P;
if (codec_id == AV_CODEC_ID_H264)
av_opt_set(outContext->priv_data, "preset", "slow", 0);
/* open it */
if (avcodec_open2(outContext, codec11, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
AVFrame *outframe = av_frame_alloc();
int nbytes = avpicture_get_size(outContext->pix_fmt,
outContext->width,
outContext->height);
uint8_t* outbuffer = (uint8_t*)av_malloc(nbytes);
//ASSOCIATE THE FRAME TO THE ALLOCATED BUFFER.
avpicture_fill((AVPicture*)outframe, outbuffer,
AV_PIX_FMT_YUV420P,
outContext->width, outContext->height);
SwsContext* swsCtx_ ;
swsCtx_= sws_getContext(pCodecCtx->width,
pCodecCtx->height,
pCodecCtx->pix_fmt,
outContext->width, outContext->height,
outContext->pix_fmt,
SWS_BICUBIC, NULL, NULL, NULL);
//HERE WE START PULLING PACKETS FROM THE SPECIFIED FORMAT CONTEXT.
while(av_read_frame(pFormatCtx, packet)>=0)
{
if(packet->stream_index==videoindex)
{
ret= avcodec_decode_video2(pCodecCtx,
pFrame,
&got_picture,packet );
if(ret < 0)
{
printf("Decode Error.\n");
return -1;
}
if(got_picture)
{
sws_scale(swsCtx_, pFrame->data, pFrame->linesize,
0, pCodecCtx->height, outframe->data,
outframe->linesize);
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
ret = avcodec_encode_video2(outContext, &pkt, outframe, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
}
av_free_packet(packet);
}//THE LOOP TO PULL PACKETS FROM THE FORMAT CONTEXT ENDS HERE.
//
/* get the delayed frames */
for (got_output = 1; got_output; i++) {
//fflush(stdout);
ret = avcodec_encode_video2(outContext, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* add sequence end code to have a real mpeg file */
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_close(outContext);
av_free(outContext);
//av_freep(&frame->data[0]);
//av_frame_free(&frame);
//THIS WAS ADDED LATER
av_free(outbuffer);
avcodec_close(pCodecCtx);
avformat_close_input(&pFormatCtx);
return 0;
}Thank you for your time.
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FFMPEG Encoding Issues
16 octobre 2014, par madprogrammer2015I am having issues encoding screen captures, into a h.264 file for viewing. The program below is cobbled together from examples here and here. The first example, uses an older version of the ffmpeg api. So I tried to update that example for use in my program. The file is created and has something written to it, but when I view the file. The encoded images are all distorted. I am able to run the video encoding example from the ffmpeg api successfully. This is my first time posting, so if I missed anything please let me know.
I appreciate any assistance that is given.
My program :
#include
#include <string>
#include <sstream>
#include
#include <iostream>
#include
extern "C"{
#include
#include <libavcodec></libavcodec>avcodec.h>
#include <libavutil></libavutil>imgutils.h>
#include <libswscale></libswscale>swscale.h>
#include <libavutil></libavutil>opt.h>
}
using namespace std;
void ScreenShot(const char* BmpName, uint8_t *frame)
{
HWND DesktopHwnd = GetDesktopWindow();
RECT DesktopParams;
HDC DevC = GetDC(DesktopHwnd);
GetWindowRect(DesktopHwnd,&DesktopParams);
DWORD Width = DesktopParams.right - DesktopParams.left;
DWORD Height = DesktopParams.bottom - DesktopParams.top;
DWORD FileSize = sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+(sizeof(RGBTRIPLE)+1*(Width*Height*4));
char *BmpFileData = (char*)GlobalAlloc(0x0040,FileSize);
PBITMAPFILEHEADER BFileHeader = (PBITMAPFILEHEADER)BmpFileData;
PBITMAPINFOHEADER BInfoHeader = (PBITMAPINFOHEADER)&BmpFileData[sizeof(BITMAPFILEHEADER)];
BFileHeader->bfType = 0x4D42; // BM
BFileHeader->bfSize = sizeof(BITMAPFILEHEADER);
BFileHeader->bfOffBits = sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
BInfoHeader->biSize = sizeof(BITMAPINFOHEADER);
BInfoHeader->biPlanes = 1;
BInfoHeader->biBitCount = 32;
BInfoHeader->biCompression = BI_RGB;
BInfoHeader->biHeight = Height;
BInfoHeader->biWidth = Width;
RGBTRIPLE *Image = (RGBTRIPLE*)&BmpFileData[sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)];
RGBTRIPLE color;
//pPixels = (RGBQUAD **)new RGBQUAD[sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER)];
int start = clock();
HDC CaptureDC = CreateCompatibleDC(DevC);
HBITMAP CaptureBitmap = CreateCompatibleBitmap(DevC,Width,Height);
SelectObject(CaptureDC,CaptureBitmap);
BitBlt(CaptureDC,0,0,Width,Height,DevC,0,0,SRCCOPY|CAPTUREBLT);
GetDIBits(CaptureDC,CaptureBitmap,0,Height,frame,(LPBITMAPINFO)BInfoHeader, DIB_RGB_COLORS);
int end = clock();
cout << "it took " << end - start << " to capture a frame" << endl;
DWORD Junk;
HANDLE FH = CreateFileA(BmpName,GENERIC_WRITE,FILE_SHARE_WRITE,0,CREATE_ALWAYS,0,0);
WriteFile(FH,BmpFileData,FileSize,&Junk,0);
CloseHandle(FH);
GlobalFree(BmpFileData);
}
void video_encode_example(const char *filename, int codec_id)
{
AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y, got_output;
FILE *f;
AVFrame *frame;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
printf("Encode video file %s\n", filename);
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder(AV_CODEC_ID_H264);
if (!codec) {
fprintf(stderr, "Codec not found\n");
cin.get();
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
cin.get();
exit(1);
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 352;
c->height = 288;
/* frames per second */
c->time_base.num=1;
c->time_base.den = 25;
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = AV_PIX_FMT_YUV420P;
if(codec_id == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "slow", 0);
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
frame = av_frame_alloc();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;
/* the image can be allocated by any means and av_image_alloc() is
just the most convenient way if av_malloc() is to be used */
ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, c->pix_fmt, 32);
if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
/* encode 1 second of video */
for(i=0;i<250;i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0;yheight;y++) {
for(x=0;xwidth;x++) {
frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;yheight/2;y++) {
for(x=0;xwidth/2;x++) {
frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2;
frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5;
}
}
frame->pts = i;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* get the delayed frames */
for (got_output = 1; got_output; i++) {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* add sequence end code to have a real mpeg file */
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_close(c);
av_free(c);
av_freep(&frame->data[0]);
av_frame_free(&frame);
printf("\n");
}
void write_video_frame()
{
}
int lineSizeOfFrame(int width)
{
return (width*24 + 31)/32 * 4;//((width*24 / 8) + 3) & ~3;//(width*24 + 31)/32 * 4;
}
int getScreenshotWithCursor(uint8_t* frame)
{
int successful = 0;
HDC screen, bitmapDC;
HBITMAP screen_bitmap;
screen = GetDC(NULL);
RECT DesktopParams;
HWND desktop = GetDesktopWindow();
GetWindowRect(desktop, &DesktopParams);
int width = DesktopParams.right;
int height = DesktopParams.bottom;
bitmapDC = CreateCompatibleDC(screen);
screen_bitmap = CreateCompatibleBitmap(screen, width, height);
SelectObject(bitmapDC, screen_bitmap);
if (BitBlt(bitmapDC, 0, 0, width, height, screen, 0, 0, SRCCOPY))
{
int pos_x, pos_y;
HICON hcur;
ICONINFO icon_info;
CURSORINFO cursor_info;
cursor_info.cbSize = sizeof(CURSORINFO);
if (GetCursorInfo(&cursor_info))
{
if (cursor_info.flags == CURSOR_SHOWING)
{
hcur = CopyIcon(cursor_info.hCursor);
if (GetIconInfo(hcur, &icon_info))
{
pos_x = cursor_info.ptScreenPos.x - icon_info.xHotspot;
pos_y = cursor_info.ptScreenPos.y - icon_info.yHotspot;
DrawIcon(bitmapDC, pos_x, pos_y, hcur);
if (icon_info.hbmColor) DeleteObject(icon_info.hbmColor);
if (icon_info.hbmMask) DeleteObject(icon_info.hbmMask);
}
}
}
int header_size = sizeof(BITMAPINFOHEADER) + 256*sizeof(RGBQUAD);
size_t line_size = lineSizeOfFrame(width);
PBITMAPINFO lpbi = (PBITMAPINFO) malloc(header_size);
lpbi->bmiHeader.biSize = header_size;
lpbi->bmiHeader.biWidth = width;
lpbi->bmiHeader.biHeight = height;
lpbi->bmiHeader.biPlanes = 1;
lpbi->bmiHeader.biBitCount = 24;
lpbi->bmiHeader.biCompression = BI_RGB;
lpbi->bmiHeader.biSizeImage = height*line_size;
lpbi->bmiHeader.biXPelsPerMeter = 0;
lpbi->bmiHeader.biYPelsPerMeter = 0;
lpbi->bmiHeader.biClrUsed = 0;
lpbi->bmiHeader.biClrImportant = 0;
if (GetDIBits(bitmapDC, screen_bitmap, 0, height, (LPVOID)frame, lpbi, DIB_RGB_COLORS))
{
int i;
uint8_t *buf_begin = frame;
uint8_t *buf_end = frame + line_size*(lpbi->bmiHeader.biHeight - 1);
void *temp = malloc(line_size);
for (i = 0; i < lpbi->bmiHeader.biHeight / 2; ++i)
{
memcpy(temp, buf_begin, line_size);
memcpy(buf_begin, buf_end, line_size);
memcpy(buf_end, temp, line_size);
buf_begin += line_size;
buf_end -= line_size;
}
cout << *buf_begin << endl;
free(temp);
successful = 1;
}
free(lpbi);
}
DeleteObject(screen_bitmap);
DeleteDC(bitmapDC);
ReleaseDC(NULL, screen);
return successful;
}
int main()
{
RECT DesktopParams;
HWND desktop = GetDesktopWindow();
GetWindowRect(desktop, &DesktopParams);
int width = DesktopParams.right;
int height = DesktopParams.bottom;
uint8_t *frame = (uint8_t *)malloc(width * height);
AVCodec *codec;
AVCodecContext *codecContext = NULL;
AVPacket packet;
FILE *f;
AVFrame *pictureYUV = NULL;
AVFrame *pictureRGB;
avcodec_register_all();
codec = avcodec_find_encoder(AV_CODEC_ID_H264);
if(!codec)
{
cout << "codec not found!" << endl;
cin.get();
return 1;
}
else
{
cout << "codec h265 found!" << endl;
}
codecContext = avcodec_alloc_context3(codec);
codecContext->bit_rate = width * height * 4;
codecContext->width = width;
codecContext->height = height;
codecContext->time_base.num = 1;
codecContext->time_base.den = 250;
codecContext->gop_size = 10;
codecContext->max_b_frames = 1;
codecContext->keyint_min = 1;
codecContext->i_quant_factor = (float)0.71; // qscale factor between P and I frames
codecContext->b_frame_strategy = 20; ///// find out exactly what this does
codecContext->qcompress = (float)0.6; ///// find out exactly what this does
codecContext->qmin = 20; // minimum quantizer
codecContext->qmax = 51; // maximum quantizer
codecContext->max_qdiff = 4; // maximum quantizer difference between frames
codecContext->refs = 4; // number of reference frames
codecContext->trellis = 1;
codecContext->pix_fmt = AV_PIX_FMT_YUV420P;
codecContext->codec_id = AV_CODEC_ID_H264;
codecContext->codec_type = AVMEDIA_TYPE_VIDEO;
if(avcodec_open2(codecContext, codec, NULL) < 0)
{
cout << "couldn't open codec" << endl;
cout << stderr << endl;
cin.get();
return 1;
}
else
{
cout << "opened h265 codec!" << endl;
cin.get();
}
f = fopen("test.h264", "wb");
if(!f)
{
cout << "Unable to open file" << endl;
return 1;
}
struct SwsContext *img_convert_ctx = sws_getContext(codecContext->width, codecContext->height, PIX_FMT_RGB32, codecContext->width,
codecContext->height, codecContext->pix_fmt, SWS_BILINEAR, NULL, NULL, NULL);
int got_output = 0, i = 0;
uint8_t encode[] = { 0, 0, 1, 0xb7 };
try
{
for(i = 0; i < codecContext->time_base.den; i++)
{
av_init_packet(&packet);
packet.data = NULL;
packet.size = 0;
pictureRGB = av_frame_alloc();
pictureYUV = av_frame_alloc();
getScreenshotWithCursor(frame);
//ScreenShot("example.bmp", frame);
int nbytes = avpicture_get_size(AV_PIX_FMT_YUV420P, codecContext->width, codecContext->height); // allocating outbuffer
uint8_t* outbuffer = (uint8_t*)av_malloc(nbytes*sizeof(uint8_t));
pictureRGB = av_frame_alloc();
pictureYUV = av_frame_alloc();
avpicture_fill((AVPicture*)pictureRGB, frame, PIX_FMT_RGB32, codecContext->width, codecContext->height); // fill image with input screenshot
avpicture_fill((AVPicture*)pictureYUV, outbuffer, PIX_FMT_YUV420P, codecContext->width, codecContext->height);
av_image_alloc(pictureYUV->data, pictureYUV->linesize, codecContext->width, codecContext->height, codecContext->pix_fmt, 32);
sws_scale(img_convert_ctx, pictureRGB->data, pictureRGB->linesize, 0, codecContext->height, pictureYUV->data, pictureYUV->linesize);
pictureYUV->pts = i;
avcodec_encode_video2(codecContext, &packet, pictureYUV, &got_output);
if(got_output)
{
printf("Write frame %3d (size=%5d)\n", i, packet.size);
fwrite(packet.data, 1, packet.size, f);
av_free_packet(&packet);
}
//av_frame_free(&pictureRGB);
//av_frame_free(&pictureYUV);
}
for(got_output = 1; got_output; i++)
{
fflush(stdout);
avcodec_encode_video2(codecContext, &packet, NULL, &got_output);
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, packet.size);
fwrite(packet.data, 1, packet.size, f);
av_free_packet(&packet);
}
}
}
catch(std::exception ex)
{
cout << ex.what() << endl;
}
avcodec_close(codecContext);
av_free(codecContext);
av_freep(&pictureYUV->data[0]);
//av_frame_free(&picture);
fwrite(encode, 1, sizeof(encode), f);
fclose(f);
cin.get();
return 0;
}
</iostream></sstream></string> -
What am I doing wrong with my audio writing in ffmpeg ? [on hold]
12 septembre 2014, par Michael NguyenI’m trying to splice multiple video sources into one. I’m having trouble understanding the audio portion of it. Rather I should say, the audio part of my code doesn’t seem to work. I don’t understand it. Could somebody help me understand what I am doing wrong ? The method doing all the work is called renderMovieRequest
Thanks in advance.
My entire code can be found here : http://pastebin.com/rAZkU3XZ
Any help would be appreciated.
below is a snippet of the code (it’s too long otherwise)int64_t timeBase;
bool seek(AVFormatContext *pFormatCtx, int frameIndex){
if(!pFormatCtx)
return false;
int64_t seekTarget = int64_t(frameIndex) * timeBase;
if(av_seek_frame(pFormatCtx, -1, seekTarget, AVSEEK_FLAG_ANY) < 0) {
ELOG("av_seek_frame failed.");
return false;
}
return true;
}
typedef struct OutputStream {
AVStream *st;
/* 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 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)) {
ELOG("Could not find encoder for '%s'\n", avcodec_get_name(codec_id));
return;
}
ost->st = avformat_new_stream(oc, *codec);
if (!ost->st) {
ELOG("Could not allocate stream\n");
return;
}
ost->st->id = oc->nb_streams-1;
c = ost->st->codec;
switch ((*codec)->type) {
case AVMEDIA_TYPE_AUDIO:
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:
c->codec_id = codec_id;
c->bit_rate = 400000;
/* Resolution must be a multiple of two. */
// c->width = 352;
// c->height = 288;
c->width = 1280;
c->height = 720;
/* 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;
}
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;
}
break;
default:
break;
}
/* Some formats want stream headers to be separate. */
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
c->flags |= CODEC_FLAG_GLOBAL_HEADER;
}
/**************************************************************/
/* audio output */
static AVFrame *alloc_audio_frame(enum AVSampleFormat sample_fmt,
uint64_t channel_layout,
int sample_rate, int nb_samples)
{
AVFrame *frame = av_frame_alloc();
int ret;
if (!frame) {
fprintf(stderr, "Error allocating an audio frame\n");
exit(1);
}
frame->format = sample_fmt;
frame->channel_layout = channel_layout;
frame->sample_rate = sample_rate;
frame->nb_samples = nb_samples;
if (nb_samples) {
ret = av_frame_get_buffer(frame, 0);
if (ret < 0) {
fprintf(stderr, "Error allocating an audio buffer\n");
exit(1);
}
}
return frame;
}
static int open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
{
AVCodecContext *c;
int nb_samples;
int ret;
AVDictionary *opt = NULL;
c = ost->st->codec;
/* open it */
av_dict_copy(&opt, opt_arg, 0);
ret = avcodec_open2(c, codec, &opt);
av_dict_free(&opt);
if (ret < 0) {
ELOG("Could not open audio codec: %s\n", av_err2str(ret));
return ret;
}
/* init signal generator */
ost->t = 0;
ost->tincr = 2 * M_PI * 110.0 / c->sample_rate;
/* increment frequency by 110 Hz per second */
ost->tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
if (c->codec->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE)
nb_samples = 10000;
else
nb_samples = c->frame_size;
ost->frame = alloc_audio_frame(c->sample_fmt, c->channel_layout,
c->sample_rate, nb_samples);
ost->tmp_frame = alloc_audio_frame(AV_SAMPLE_FMT_S16, c->channel_layout,
c->sample_rate, nb_samples);
/* create resampler context */
ost->swr_ctx = swr_alloc();
if (!ost->swr_ctx) {
ELOG("Could not allocate resampler context\n");
return -300;
}
/* set options */
av_opt_set_int (ost->swr_ctx, "in_channel_count", c->channels, 0);
av_opt_set_int (ost->swr_ctx, "in_sample_rate", c->sample_rate, 0);
av_opt_set_sample_fmt(ost->swr_ctx, "in_sample_fmt", AV_SAMPLE_FMT_S16, 0);
av_opt_set_int (ost->swr_ctx, "out_channel_count", c->channels, 0);
av_opt_set_int (ost->swr_ctx, "out_sample_rate", c->sample_rate, 0);
av_opt_set_sample_fmt(ost->swr_ctx, "out_sample_fmt", c->sample_fmt, 0);
/* initialize the resampling context */
if ((ret = swr_init(ost->swr_ctx)) < 0) {
ELOG("Failed to initialize the resampling context: %i\n", ret);
return ret;
}
return 0;
}
/*
* encode one audio frame and send it to the muxer
* return 1 when encoding is finished, 0 otherwise
*/
static int write_audio_frame(AVFormatContext *oc, OutputStream *ost, AVFrame *frame)
{
AVCodecContext *c;
AVPacket pkt = { 0 }; // data and size must be 0;
// AVFrame *frame;
int ret;
int got_packet;
int dst_nb_samples;
av_init_packet(&pkt);
c = ost->st->codec;
// frame = get_audio_frame(ost);
if (frame) {
/* convert samples from native format to destination codec format, using the resampler */
/* compute destination number of samples */
dst_nb_samples = av_rescale_rnd(swr_get_delay(ost->swr_ctx, c->sample_rate) + frame->nb_samples,
c->sample_rate, c->sample_rate, AV_ROUND_UP);
av_assert0(dst_nb_samples == frame->nb_samples);
/* 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(ost->frame);
if (ret < 0) {
ELOG("Unable to prepare frame for writing: Error code: %s", av_err2str(ret));
return ret;
}
/* convert to destination format */
ret = swr_convert(ost->swr_ctx,
ost->frame->data, dst_nb_samples,
(const uint8_t **)frame->data, frame->nb_samples);
if (ret < 0) {
ELOG("Error while converting: %s\n", av_err2str(ret));
return -1;
}
frame = ost->frame;
frame->pts = av_rescale_q(ost->samples_count, (AVRational){1, c->sample_rate}, c->time_base);
ost->samples_count += dst_nb_samples;
}
ret = avcodec_encode_audio2(c, &pkt, frame, &got_packet);
if (ret < 0) {
ELOG("Error encoding audio frame: %s\n", av_err2str(ret));
return -1;
}
if (got_packet) {
ret = write_frame(oc, &c->time_base, ost->st, &pkt);
if (ret < 0) {
ELOG( "Error while writing audio frame: %s\n", av_err2str(ret));
return -1;
}
}
return (frame || got_packet) ? 0 : 1;
}
/**************************************************************/
/* 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 int open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
{
int ret;
AVCodecContext *c = ost->st->codec;
AVDictionary *opt = NULL;
av_dict_copy(&opt, opt_arg, 0);
/* open the codec */
ret = avcodec_open2(c, codec, &opt);
av_dict_free(&opt);
if (ret < 0) {
ELOG("Could not open video codec: %s\n", av_err2str(ret));
return ret;
}
/* allocate and init a re-usable frame */
DLOG("Allocate and init a are-usable frame: %i x %i Format: %i", c->width, c->height, c->pix_fmt);
ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
if (!ost->frame) {
ELOG("Could not allocate video frame\n");
return -100;
}
/* 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) {
DLOG("input format is not YUV420P converting to size %i x %i", c->width, c->height);
ost->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
if (!ost->tmp_frame) {
ELOG("Could not allocate temporary picture\n");
return -200;
}
}
return 0;
}
/*
* 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, AVFrame *frame)
{
int ret;
AVCodecContext *c;
int got_packet = 0;
c = ost->st->codec;
if (oc->oformat->flags & AVFMT_RAWPICTURE) {
/* a hack to avoid data copy with some raw video muxers */
AVPacket pkt;
av_init_packet(&pkt);
if (!frame)
return 1;
pkt.flags |= AV_PKT_FLAG_KEY;
pkt.stream_index = ost->st->index;
pkt.data = (uint8_t *)frame;
pkt.size = sizeof(AVPicture);
pkt.pts = pkt.dts = frame->pts;
av_packet_rescale_ts(&pkt, c->time_base, ost->st->time_base);
ret = av_interleaved_write_frame(oc, &pkt);
} else {
AVPacket pkt = { 0 };
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_close(ost->st->codec);
av_frame_free(&ost->frame);
av_frame_free(&ost->tmp_frame);
sws_freeContext(ost->sws_ctx);
swr_free(&ost->swr_ctx);
}
int renderMovieRequest(movieRequest *movieRequestObj, string outputPath) {
AVOutputFormat *ofmt = NULL;
AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
AVFormatContext *pFormatCtx = NULL;
AVCodec *audio_codec, *video_codec;
OutputStream video_st = { 0 }, audio_st = { 0 };
size_t i;
int videoStream, audioStream;
AVCodecContext *pCodecCtx = NULL;
AVCodec *pCodec = NULL;
AVFrame *pFrame = NULL;
AVFrame *pFrameRGB = NULL;
AVPacket packet = { 0 };
int frameFinished;
int audioFrameFinished;
int numBytes;
uint8_t *buffer = NULL;
AVDictionary *optionsDict = NULL;
AVDictionary *opt = NULL;
struct SwsContext *sws_ctx = NULL;
const char *in_filename, *out_filename;
int ret;
int have_audio = 0, have_video = 0;
int encode_audio = 0, encode_video = 0;
processProtobuf(movieRequestObj);
out_filename = outputPath.c_str();
av_register_all();
DLOG("attempting to create context for output file %s", out_filename);
avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, out_filename);
if (!ofmt_ctx) {
ELOG("Could not create output context\n");
ret = AVERROR_UNKNOWN;
return ret; //goto end;
}
ofmt = ofmt_ctx->oformat;
/* Add the audio and video streams using the default format codecs
* and initialize the codecs. */
if (ofmt->video_codec != AV_CODEC_ID_NONE) {
add_stream(&video_st, ofmt_ctx, &video_codec, ofmt->video_codec);
have_video = 1;
encode_video = 1;
}
if (ofmt->audio_codec != AV_CODEC_ID_NONE) {
add_stream(&audio_st, ofmt_ctx, &audio_codec, ofmt->audio_codec);
have_audio = 1;
encode_audio = 1;
}
DLOG("allocate encode buffers");
/* 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(ofmt_ctx, video_codec, &video_st, opt);
if (have_audio) {
DLOG("Opening audio codec");
open_audio(ofmt_ctx, audio_codec, &audio_st, opt);
}
DLOG("open output file for writing");
/* open the output file, if needed */
if (!(ofmt->flags & AVFMT_NOFILE)) {
ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
if (ret < 0) {
ELOG( "Could not open '%s': %s\n", out_filename, av_err2str(ret));
return 1;
}
}
/* Write the stream header, if any. */
ret = avformat_write_header(ofmt_ctx, &opt);
if (ret < 0) {
ELOG("Error occurred when opening output file: %s\n", av_err2str(ret));
return 1;
}
vector<clipshptr> * clips = &(movieRequestObj->clips);
DLOG("ready to process clips: %i", clips->size());
for (size_t clipIdx = 0; clipIdx < clips->size(); ++clipIdx) {
shared_ptr<clip> currentClip = clips->at(clipIdx);
switch (currentClip->getClipType()) {
case VIDEO_CLIP: {
DLOG("clip is a video clip...");
shared_ptr<videoclip> vidClip = dynamic_pointer_cast<videoclip>(clips->at(clipIdx));
if (vidClip->shouldHaveSegments) {
// open the file for reading and create a temporary file for output
in_filename = vidClip->vidFileName.c_str();
DLOG("Opening %s for reading", in_filename);
if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 0) {
ELOG("Could not open input file '%s'", in_filename);
return ret; //goto end;
}
if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
ELOG("Failed to retrieve input stream information");
return ret; //goto end;
}
av_dump_format(ifmt_ctx, 0, in_filename, 0);
videoStream = -1;
audioStream = -1;
// setup input format context and output format context;
// AVStream *video_in_stream = NULL;
for (i = 0; i < ifmt_ctx->nb_streams; i++) {
if(ifmt_ctx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO) {
videoStream=i;
// video_in_stream = ifmt_ctx->streams[i];
}
else if(ifmt_ctx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO) {
audioStream=i;
// video_in_stream = ifmt_ctx->streams[i];
}
}
if (videoStream == -1) {
DLOG("not a video stream.");
continue;
}
// Get a pointer to the codec context for the video stream
pCodecCtx = ifmt_ctx->streams[videoStream]->codec;
if (pCodecCtx == NULL) {
ELOG("Error in getting pointer to codec for vidstream");
}
DLOG("Input pixel format: %i ", pCodecCtx->pix_fmt);
// Find the decoder for the video stream
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
if(pCodec==NULL) {
ELOG("Unsupported codec!\n");
return -1; // Codec not found
}
// Open codec
if(avcodec_open2(pCodecCtx, pCodec, &optionsDict)<0) {
ELOG("Unable to open codec");
return -1; // Could not open codec
}
// get the timebase
timeBase = (int64_t(pCodecCtx->time_base.num) * AV_TIME_BASE) / int64_t(pCodecCtx->time_base.den);
// Allocate video frame
pFrame=av_frame_alloc();
// Allocate an AVFrame structure
pFrameRGB=av_frame_alloc();
if(pFrameRGB==NULL)
return -1;
// Determine required buffer size and allocate buffer
// numBytes=avpicture_get_size(PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height);
numBytes = avpicture_get_size(PIX_FMT_RGB24, movieRequestObj->width, movieRequestObj->height);
DLOG("Buffer size allocated: %i x %i: %i ", movieRequestObj->width, movieRequestObj->height, numBytes);
buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
sws_ctx = sws_getContext
(
pCodecCtx->width,
pCodecCtx->height,
pCodecCtx->pix_fmt,
movieRequestObj->width,
movieRequestObj->height,
PIX_FMT_RGB24,
SWS_BILINEAR,
NULL,
NULL,
NULL
);
// Assign appropriate parts of buffer to image planes in pFrameRGB
// Note that pFrameRGB is an AVFrame, but AVFrame is a superset
// of AVPicture
avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24, movieRequestObj->width, movieRequestObj->height);
size_t numSegments = vidClip->segments.size();
DLOG("Found %i segments to process", numSegments);
for (size_t segmentIdx = 0; segmentIdx < numSegments; ++segmentIdx) {
// seek to the right position
int frameOffset = vidClip->segments.at(segmentIdx).first;
int clipDuration = vidClip->segments.at(segmentIdx).second;
DLOG("Starting Frame Number: %i Duration: %i", frameOffset, clipDuration);
seek(ifmt_ctx, frameOffset);
// loop for X frames where X is < frameOffset + clipDuration; clipDuration is the length of the clip in terms of frames
for (int frameIdx = frameOffset; frameIdx < (frameOffset + clipDuration); ++frameIdx) {
av_init_packet(&packet);
int avReadResult = 0;
int continueRecording = 1;
while ((continueRecording == 1) && (frameIdx < (frameOffset + clipDuration) )) {
avReadResult = av_read_frame(ifmt_ctx, &packet);
if(avReadResult != 0){
if (avReadResult != AVERROR_EOF) {
ELOG("av_read_frame error: %i", avReadResult );
} else {
ILOG("End of input file");
}
continueRecording = 0;
}
// Is this a packet from the video stream?
if(packet.stream_index==videoStream) {
// Decode video frame
avcodec_decode_video2(pCodecCtx, pFrameRGB, &frameFinished, &packet);
// Did we get a video frame?
if(frameFinished) {
// Convert the image from its native format to RGB
sws_scale
(
sws_ctx,
(uint8_t const * const *)pFrame->data,
pFrame->linesize,
0,
pCodecCtx->height,
pFrameRGB->data,
pFrameRGB->linesize
);
write_video_frame(ofmt_ctx, &video_st, pFrameRGB);
frameIdx++;
}
}
else if (packet.stream_index == audioStream) {
// Decode audio frame
DLOG("Audio frame found");
avcodec_decode_audio4(pCodecCtx, pFrameRGB, &audioFrameFinished, &packet);
if (audioFrameFinished) {
// write the audio frame to file
write_audio_frame(ofmt_ctx, &audio_st, pFrameRGB);
}
}
// Free the packet that was allocated by av_read_frame
av_free_packet(&packet);
}
// Free the RGB image
}
}
DLOG("Cleaning up frame allocations");
av_free(buffer);
av_free(pFrameRGB);
// Free the YUV frame
av_free(pFrame);
} // end video clip processing
}
break;
case TITLE_CLIP: {
}
break;
default:
ELOG("Failed to identify clip");
break;
} // end switch statement
DLOG("Finished processing clip #%i", clipIdx);
avformat_close_input(&ifmt_ctx);
} // end main for loop -> clip iteration
/* Write the trailer, if any. The trailer must be written before you
* close the CodecContexts open when you wrote the header; otherwise
* av_write_trailer() may try to use memory that was freed on
* av_codec_close(). */
av_write_trailer(ofmt_ctx);
/* Close each codec. */
if (have_video)
close_stream(ofmt_ctx, &video_st);
if (have_audio)
close_stream(ofmt_ctx, &audio_st);
if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE)) {
/* Close the output file. */
avio_close(ofmt_ctx->pb);
}
DLOG("Closing input format context");
avformat_close_input(&ifmt_ctx);
DLOG("Free ouptut format context");
avformat_free_context(ofmt_ctx);
if (ret < 0 && ret != AVERROR_EOF) {
ELOG( "Error occurred: %s\n", av_err2str(ret));
return 1;
}
return 0;
}
#ifdef __cplusplus
}
#endif
</videoclip></videoclip></clip></clipshptr>
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