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Autres articles (111)
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MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...) -
Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...)
Sur d’autres sites (9595)
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ffmpeg and streaming video - frame time issue
6 mai 2014, par 4ntoineI’ve compiled ffmpeg-android (https://github.com/appunite/AndroidFFmpeg) and it works for files.
The problem is that it shows nothing for network streams (both rtmp and hls) as frame timestamp is too big and it seems to be not from video beginning (as for file). Then it waits for the first frame time which for network stream is too big :player_decode_video copying...
05-05 18:11:26.994: INFO/player.c(16998): player_decode_video Decoded video frame: 568.233000, time_base: 51140970
05-05 18:11:26.994: INFO/player.c(16998): player_wait_for_frame[0] start
...
05-05 18:11:30.587: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (568.233000) - (0.000977)
05-05 18:11:30.587: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: 568232023
05-05 18:11:31.088: INFO/player.c(16998): player_wait_for_frame[0] timeout
05-05 18:11:31.088: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (568.233000) - (0.501542)
05-05 18:11:31.088: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: 567731458
05-05 18:11:31.588: INFO/player.c(16998): player_wait_for_frame[0] timeout
05-05 18:11:31.588: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (568.233000) - (1.002778)
05-05 18:11:31.588: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: 567230222
05-05 18:11:32.089: INFO/player.c(16998): player_wait_for_frame[0] timeout
05-05 18:11:32.089: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (568.233000) - (1.504563)
05-05 18:11:32.089: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: 566728437
05-05 18:11:32.590: INFO/player.c(16998): player_wait_for_frame[0] timeout
05-05 18:11:32.590: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (568.233000) - (2.005708)
05-05 18:11:32.590: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: 566227292also i can’t figure out what timestamp for frame for network stream means (for file frames it’s a time from video beginning)
for file it’s clear : time_base is frame number and timestamp is time from video beginning and it plays the files :
player_decode_video Decoded video frame: 0.320000, time_base: 8
05-05 18:32:42.344: INFO/player.c(16998): player_wait_for_frame[0] start
05-05 18:32:42.344: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (0.320000) - (0.344337)
05-05 18:32:42.344: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: -24337
05-05 18:32:42.344: INFO/player.c(16998): player_wait_for_frame[0] finish[0]
05-05 18:32:42.344: INFO/player.c(16998): player_update_time: 0.346169/4.000000
05-05 18:32:42.344: INFO/player.c(16998): player_decode waiting for frame[0]
05-05 18:32:42.344: INFO/player.c(16998): player_decode decoding frame[0]
05-05 18:32:42.344: INFO/player.c(16998): player_decode_video decoding
05-05 18:32:42.344: INFO/player.c(16998): player_decode_video copy wait
05-05 18:32:42.344: INFO/player.c(16998): player_read_from_stream Read frame
05-05 18:32:42.344: INFO/player.c(16998): player_read_from_stream looking for stream
05-05 18:32:42.344: INFO/player.c(16998): player_read_from_stream stream found [0]
05-05 18:32:42.344: INFO/player.c(16998): player_read_from_stream waiting for queue
05-05 18:32:42.344: INFO/player.c(16998): Format: WINDOW_FORMAT_RGBA_8888
05-05 18:32:42.344: INFO/player.c(16998): Buffer: width: 1280, height: 720, stride: 1280
05-05 18:32:42.344: INFO/player.c(16998): player_decode_video copying...
05-05 18:32:42.425: INFO/player.c(16998): player_decode_video Decoded video frame: 0.360000, time_base: 9
05-05 18:32:42.425: INFO/player.c(16998): player_wait_for_frame[0] start
05-05 18:32:42.425: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (0.360000) - (0.427994)
05-05 18:32:42.425: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: -67994
05-05 18:32:42.425: INFO/player.c(16998): player_wait_for_frame[0] finish[0]
05-05 18:32:42.425: INFO/player.c(16998): player_update_time: 0.429214/4.000000
05-05 18:32:42.425: INFO/player.c(16998): player_decode waiting for frame[0]
05-05 18:32:42.425: INFO/player.c(16998): player_decode decoding frame[0]
05-05 18:32:42.425: INFO/player.c(16998): player_decode_video decoding
05-05 18:32:42.425: INFO/player.c(16998): player_read_from_stream Read frame
05-05 18:32:42.425: INFO/player.c(16998): player_read_from_stream looking for stream
05-05 18:32:42.425: INFO/player.c(16998): player_read_from_stream stream found [0]
05-05 18:32:42.425: INFO/player.c(16998): player_read_from_stream waiting for queue
05-05 18:32:42.425: INFO/player.c(16998): player_decode_video copy wait
05-05 18:32:42.435: INFO/player.c(16998): Format: WINDOW_FORMAT_RGBA_8888
05-05 18:32:42.435: INFO/player.c(16998): Buffer: width: 1280, height: 720, stride: 1280
05-05 18:32:42.435: INFO/player.c(16998): player_decode_video copying...
05-05 18:32:42.495: INFO/player.c(16998): player_decode_video Decoded video frame: 0.400000, time_base: 10
05-05 18:32:42.495: INFO/player.c(16998): player_wait_for_frame[0] start
05-05 18:32:42.495: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (0.400000) - (0.494742)
05-05 18:32:42.495: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: -94742
05-05 18:32:42.495: INFO/player.c(16998): player_wait_for_frame[0] finish[0]
05-05 18:32:42.495: INFO/player.c(16998): player_update_time: 0.495993/4.000000
05-05 18:32:42.495: INFO/player.c(16998): player_decode waiting for frame[0]
05-05 18:32:42.495: INFO/player.c(16998): player_decode decoding frame[0]
05-05 18:32:42.495: INFO/player.c(16998): player_decode_video decoding
05-05 18:32:42.495: INFO/player.c(16998): player_decode_video copy wait
05-05 18:32:42.495: INFO/player.c(16998): player_read_from_stream Read frame
05-05 18:32:42.495: INFO/player.c(16998): Format: WINDOW_FORMAT_RGBA_8888
05-05 18:32:42.495: INFO/player.c(16998): Buffer: width: 1280, height: 720, stride: 1280
05-05 18:32:42.495: INFO/player.c(16998): player_decode_video copying...
05-05 18:32:42.495: INFO/player.c(16998): player_read_from_stream looking for stream
05-05 18:32:42.495: INFO/player.c(16998): player_read_from_stream stream found [0]
05-05 18:32:42.495: INFO/player.c(16998): player_read_from_stream waiting for queue
05-05 18:32:42.555: INFO/player.c(16998): player_decode_video Decoded video frame: 0.440000, time_base: 11
05-05 18:32:42.555: INFO/player.c(16998): player_wait_for_frame[0] start
05-05 18:32:42.555: INFO/player.c(16998): player_wait_for_frame[0 = Video] = (0.440000) - (0.556698)
05-05 18:32:42.555: INFO/player.c(16998): player_wait_for_frame[0] Waiting for frame: sleeping: -116698
05-05 18:32:42.555: INFO/player.c(16998): player_wait_for_frame[0] finish[0]
05-05 18:32:42.555: INFO/player.c(16998): player_update_time: 0.557858/4.000000
05-05 18:32:42.555: INFO/player.c(16998): player_decode waiting for frame[0]
05-05 18:32:42.555: INFO/player.c(16998): player_read_from_stream Read frame
05-05 18:32:42.555: INFO/player.c(16998): player_read_from_stream looking for stream
05-05 18:32:42.555: INFO/player.c(16998): player_read_from_stream stream found [0]
05-05 18:32:42.555: INFO/player.c(16998): player_read_from_stream waiting for queue
05-05 18:32:42.555: INFO/player.c(16998): player_decode decoding frame[0]
05-05 18:32:42.555: INFO/player.c(16998): player_decode_video decoding
05-05 18:32:42.555: INFO/player.c(16998): player_decode_video copy wait
05-05 18:32:42.565: INFO/player.c(16998): Format: WINDOW_FORMAT_RGBA_8888
05-05 18:32:42.565: INFO/player.c(16998): Buffer: width: 1280, height: 720, stride: 1280
05-05 18:32:42.565: INFO/player.c(16998): player_decode_video copying...
05-05 18:32:42.625: INFO/player.c(16998): player_decode_video Decoded video frame: 0.480000, time_base: 12So what is the meaning of timestamp for stream and what should i change to make it playing streams (rtmp/hls - its can be opened now but it wait for frame time which is far in the future) ?
UPDATE :
int64_t pts = av_frame_get_best_effort_timestamp(frame);
if (pts == AV_NOPTS_VALUE) {
pts = 0;
}
int64_t time = av_rescale_q(pts, stream->time_base, AV_TIME_BASE_Q);
LOGI(10,
"player_decode_video Decoded video frame: %f, time_base: %" SCNd64,
time/1000000.0, pts);
player_wait_for_frame(player, time, stream_no);it extracts time which is far in future :
player_wait_for_frame[0 = Video] = (568.233000) - (0.000977)Is it correct ?
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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> -
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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