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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 (...) -
Modifier la date de publication
21 juin 2013, parComment changer la date de publication d’un média ?
Il faut au préalable rajouter un champ "Date de publication" dans le masque de formulaire adéquat :
Administrer > Configuration des masques de formulaires > Sélectionner "Un média"
Dans la rubrique "Champs à ajouter, cocher "Date de publication "
Cliquer en bas de la page sur Enregistrer -
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 (11212)
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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 ?
-
Error using FFMPEG to convert each input image into H264 compiling in Visual Studio running in MevisLab
21 février 2014, par user3012914I am creating a ML Module in MevisLab Framework, I am using FFMPEG to convert each image i get into a H264 Video and save it after I get all the frames. But unfortunately I have problem allocating the output buffer size. The application crashes when I include this in my code.If I am not including it, the output file size is just 4kb. Nothing is stored in it.
I am also not very sure whether it is correct way of getting the HBitmap into the Encoder. Would be great to have your suggestions.
My Code :
BITMAPINFO bitmapInfo;
HDC hdc;
ZeroMemory(&bitmapInfo, sizeof(bitmapInfo));
BITMAPINFOHEADER &bitmapInfoHeader = bitmapInfo.bmiHeader;
bitmapInfoHeader.biSize = sizeof(bitmapInfoHeader);
bitmapInfoHeader.biWidth = _imgWidth;
bitmapInfoHeader.biHeight = _imgHeight;
bitmapInfoHeader.biPlanes = 1;
bitmapInfoHeader.biBitCount = 24;
bitmapInfoHeader.biCompression = BI_RGB;
bitmapInfoHeader.biSizeImage = ((bitmapInfoHeader.biWidth * bitmapInfoHeader.biBitCount / 8 + 3) & 0xFFFFFFFC) * bitmapInfoHeader.biHeight;
bitmapInfoHeader.biXPelsPerMeter = 10000;
bitmapInfoHeader.biYPelsPerMeter = 10000;
bitmapInfoHeader.biClrUsed = 0;
bitmapInfoHeader.biClrImportant = 0;
//RGBQUAD* Ref = new RGBQUAD[_imgWidth,_imgHeight];
HDC hdcscreen = GetDC(0);
hdc = CreateCompatibleDC(hdcscreen);
ReleaseDC(0, hdcscreen);
_hbitmap = CreateDIBSection(hdc, (BITMAPINFO*) &bitmapInfoHeader, DIB_RGB_COLORS, &_bits, NULL, NULL);To get the BitMap I use the above code. Then I allocate the Codec Context as followed
c->bit_rate = 400000;
// resolution must be a multiple of two
c->width = 1920;
c->height = 1080;
// frames per second
frame_rate = _framesPerSecondFld->getIntValue();
//AVRational rational = {1,10};
//c->time_base = (AVRational){1,25};
//c->time_base = (AVRational){1,25};
c->gop_size = 10; // emit one intra frame every ten frames
c->max_b_frames = 1;
c->keyint_min = 1; //minimum GOP size
c->time_base.num = 1; // framerate numerator
c->time_base.den = _framesPerSecondFld->getIntValue();
c->i_quant_factor = (float)0.71; // qscale factor between P and I frames
c->pix_fmt = AV_PIX_FMT_RGB32;
std::string msg;
msg.append("Context is stored");
_messageFld->setStringValue(msg.c_str());I create the Bitmap Image as followed from the input
PagedImage *inImg = getUpdatedInputImage(0);
ML_CHECK(inImg);
ImageVector imgExt = inImg->getImageExtent();
if ((imgExt.x = _imgWidth) && (imgExt.y == _imgHeight))
{
if (((imgExt.x % 4)==0) && ((imgExt.y % 4) == 0))
{
// read out input image and write output image into video
// get input image as an array
void* imgData = NULL;
SubImageBox imageBox(imgExt); // get the whole image
getTile(inImg, imageBox, MLuint8Type, &imgData);
iData = (MLuint8*)imgData;
int r = 0; int g = 0;int b = 0;
// since we have only images with
// a z-ext of 1, we can compute the c stride as follows
int cStride = _imgWidth * _imgHeight;
uint8_t offset = 0;
// pointer into the bitmap that is
// used to write images into the avi
UCHAR* dst = (UCHAR*)_bits;
for (int y = _imgHeight-1; y >= 0; y--)
{ // reversely scan the image. if y-rows of DIB are set in normal order, no compression will be available.
offset = _imgWidth * y;
for (int x = 0; x < _imgWidth; x++)
{
if (_isGreyValueImage)
{
r = iData[offset + x];
*dst++ = (UCHAR)r;
*dst++ = (UCHAR)r;
*dst++ = (UCHAR)r;
}
else
{
b = iData[offset + x]; // windows bitmap need reverse order: bgr instead of rgb
g = iData[offset + x + cStride ];
r = iData[offset + x + cStride + cStride];
*dst++ = (UCHAR)r;
*dst++ = (UCHAR)g;
*dst++ = (UCHAR)b;
}
// alpha channel in input image is ignored
}
}Then I add it to the Encoder as followed as write as H264
in_width = c->width;
in_height = c->height;
out_width = c->width;
out_height = c->height;
ibytes = avpicture_get_size(PIX_FMT_BGR32, in_width, in_height);
obytes = avpicture_get_size(PIX_FMT_YUV420P, out_width, out_height);
outbuf_size = 100000 + c->width*c->height*(32>>3); // allocate output buffer
outbuf = static_cast(malloc(outbuf_size));
if(!obytes)
{
std::string msg;
msg.append("Bytes cannot be allocated");
_messageFld->setStringValue(msg.c_str());
}
else
{
std::string msg;
msg.append("Bytes allocation done");
_messageFld->setStringValue(msg.c_str());
}
//create buffer for the output image
inbuffer = (uint8_t*)av_malloc(ibytes);
outbuffer = (uint8_t*)av_malloc(obytes);
inbuffer = (uint8_t*)dst;
//create ffmpeg frame structures. These do not allocate space for image data,
//just the pointers and other information about the image.
AVFrame* inpic = avcodec_alloc_frame();
AVFrame* outpic = avcodec_alloc_frame();
//this will set the pointers in the frame structures to the right points in
//the input and output buffers.
avpicture_fill((AVPicture*)inpic, inbuffer, PIX_FMT_BGR32, in_width, in_height);
avpicture_fill((AVPicture*)outpic, outbuffer, PIX_FMT_YUV420P, out_width, out_height);
av_image_alloc(outpic->data, outpic->linesize, c->width, c->height, c->pix_fmt, 1);
inpic->data[0] += inpic->linesize[0]*(_imgHeight-1); // flipping frame
inpic->linesize[0] = -inpic->linesize[0];
if(!inpic)
{
std::string msg;
msg.append("Image is empty");
_messageFld->setStringValue(msg.c_str());
}
else
{
std::string msg;
msg.append("Picture has allocations");
_messageFld->setStringValue(msg.c_str());
}
//create the conversion context
fooContext = sws_getContext(in_width, in_height, PIX_FMT_BGR32, out_width, out_height, PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);
//perform the conversion
sws_scale(fooContext, inpic->data, inpic->linesize, 0, in_height, outpic->data, outpic->linesize);
//out_size = avcodec_encode_video(c, outbuf,outbuf_size, outpic);
if(!out_size)
{
std::string msg;
msg.append("Outsize is not valid");
_messageFld->setStringValue(msg.c_str());
}
else
{
std::string msg;
msg.append("Outsize is valid");
_messageFld->setStringValue(msg.c_str());
}
fwrite(outbuf, 1, out_size, f);
if(!fwrite)
{
std::string msg;
msg.append("Frames couldnt be written");
_messageFld->setStringValue(msg.c_str());
}
else
{
std::string msg;
msg.append("Frames written to the file");
_messageFld->setStringValue(msg.c_str());
}
// for (;out_size; i++)
// {
out_size = avcodec_encode_video(c, outbuf, outbuf_size, NULL);
std::string msg;
msg.append("Writing Frames");
_messageFld->setStringValue(msg.c_str());// encode the delayed frames
_numFramesFld->setIntValue(_numFramesFld->getIntValue()+1);
fwrite(outbuf, 1, out_size, f);
// }
outbuf[0] = 0x00;
outbuf[1] = 0x00; // add sequence end code to have a real mpeg file
outbuf[2] = 0x01;
outbuf[3] = 0xb7;
fwrite(outbuf, 1, 4, f);
}Then close and clean the Image Buffer and file
ML_TRACE_IN("MovieCreator::_endRecording()")
if (_numFramesFld->getIntValue() == 0)
{
_messageFld->setStringValue("Empty movie, nothing saved.");
}
else
{
_messageFld->setStringValue("Movie written to disk.");
_numFramesFld->setIntValue(0);
if (_hbitmap)
{
DeleteObject(_hbitmap);
}
if (c != NULL)
{
av_free(outbuffer);
av_free(inpic);
av_free(outpic);
fclose(f);
avcodec_close(c); // freeing memory
free(outbuf);
av_free(c);
}
}}
I think the Main Problem is over here !!
//out_size = avcodec_encode_video(c, outbuf,outbuf_size, outpic); -
FFmpeg/libav : YUV420P to RGB conversion
17 janvier 2014, par learnerI am working with Video encoding-decoding based on online tutorials. In the encoding section, the dummy image created is in YUV420P format. I need it to be in RGB or BGR format. Any idea how to do this ??
#include
#include
#include
#ifdef HAVE_AV_CONFIG_H
#undef HAVE_AV_CONFIG_H
#endif
#include "libavcodec/avcodec.h"
#include "libavutil/mathematics.h"
#define INBUF_SIZE 4096
#define AUDIO_INBUF_SIZE 20480
#define AUDIO_REFILL_THRESH 4096
/*
* Video encoding example
*/
static void video_encode_example(const char *filename)
{
AVCodec *codec;
AVCodecContext *c = NULL;
int i, out_size, size, x, y, outbuf_size;
FILE *f;
AVFrame *picture;
uint8_t *outbuf, *picture_buf;
printf("Video encoding\n");
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder(CODEC_ID_MPEG1VIDEO);
if (!codec)
{
fprintf(stderr, "codec not found\n");
exit(1);
}
c = avcodec_alloc_context();
picture = avcodec_alloc_frame();
/* 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= (AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = PIX_FMT_YUV420P;
/* open it */
if (avcodec_open(c, codec) < 0)
{
fprintf(stderr, "could not open codec\n");
exit(1);
}
f = fopen(filename, "wb");
if (!f)
{
fprintf(stderr, "could not open file! %s\n", filename);
exit(1);
}
/* alloc image and output buffer */
outbuf_size = 100000;
outbuf = malloc(outbuf_size);
size = c->width * c->height;
picture_buf = malloc((size * 3) / 2); /* size for YUV 420 */
picture->data[0] = picture_buf;
picture->data[1] = picture->data[0] + size;
picture->data[2] = picture->data[1] + size / 4;
picture->linesize[0] = c->width;
picture->linesize[1] = c->width / 2;
picture->linesize[2] = c->width / 2;
/* encode 1 second of video */
for(i=0; i<25; i++)
{
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0; y < c->height; y++)
{
for(x=0; x < c->width; x++)
{
picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0; y < c->height/2; y++)
{
for(x=0; x < c->width/2; x++)
{
picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
}
}
/* encode the image */
out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture);
printf("encoding frame %3d (size=%5d)\n", i, out_size);
fwrite(outbuf, 1, out_size, f);
}
/* get the delayed frames */
for(; out_size; i++)
{
fflush(stdout);
out_size = avcodec_encode_video(c, outbuf, outbuf_size, NULL);
printf("write frame %3d (size=%5d)\n", i, out_size);
fwrite(outbuf, 1, out_size, f);
}
/* add sequence end code to have a real mpeg file */
outbuf[0] = 0x00;
outbuf[1] = 0x00;
outbuf[2] = 0x01;
outbuf[3] = 0xb7;
fwrite(outbuf, 1, 4, f);
fclose(f);
free(picture_buf);
free(outbuf);
avcodec_close(c);
av_free(c);
av_free(picture);
printf("\n");
}
/*
* Video decoding example
*/
static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
char *filename)
{
FILE *f;
int i;
f=fopen(filename,"w");
fprintf(f,"P5\n%d %d\n%d\n",xsize,ysize,255);
for(i=0; i* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */
memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE);
printf("Video decoding\n");
/* find the mpeg1 video decoder */
codec = avcodec_find_decoder(CODEC_ID_MPEG1VIDEO);
if (!codec) {
fprintf(stderr, "codec not found\n");
exit(1);
}
c = avcodec_alloc_context();
picture = avcodec_alloc_frame();
if(codec->capabilities&CODEC_CAP_TRUNCATED)
c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */
/* For some codecs, such as msmpeg4 and mpeg4, width and height
MUST be initialized there because this information is not
available in the bitstream. */
/* open it */
if (avcodec_open(c, codec) < 0) {
fprintf(stderr, "could not open codec\n");
exit(1);
}
/* the codec gives us the frame size, in samples */
f = fopen(filename, "rb");
if (!f) {
fprintf(stderr, "could not open file! %s\n", filename);
exit(1);
}
frame = 0;
for(;;) {
avpkt.size = fread(inbuf, 1, INBUF_SIZE, f);
if (avpkt.size == 0)
break;
/* NOTE1: some codecs are stream based (mpegvideo, mpegaudio)
and this is the only method to use them because you cannot
know the compressed data size before analysing it.
BUT some other codecs (msmpeg4, mpeg4) are inherently frame
based, so you must call them with all the data for one
frame exactly. You must also initialize 'width' and
'height' before initializing them. */
/* NOTE2: some codecs allow the raw parameters (frame size,
sample rate) to be changed at any frame. We handle this, so
you should also take care of it */
/* here, we use a stream based decoder (mpeg1video), so we
feed decoder and see if it could decode a frame */
avpkt.data = inbuf;
while (avpkt.size > 0)
{
len = avcodec_decode_video2(c, picture, &got_picture, &avpkt);
if (len < 0)
{
fprintf(stderr, "Error while decoding frame %d\n", frame);
exit(1);
}
if (got_picture)
{
printf("saving frame %3d\n", frame);
fflush(stdout);
/* the picture is allocated by the decoder. no need to
free it */
snprintf(buf, sizeof(buf), outfilename, frame);
pgm_save(picture->data[0], picture->linesize[0],
c->width, c->height, buf);
frame++;
}
avpkt.size -= len;
avpkt.data += len;
}
}
/* some codecs, such as MPEG, transmit the I and P frame with a
latency of one frame. You must do the following to have a
chance to get the last frame of the video */
avpkt.data = NULL;
avpkt.size = 0;
len = avcodec_decode_video2(c, picture, &got_picture, &avpkt);
if (got_picture)
{
printf("saving last frame %3d\n", frame);
fflush(stdout);
/* the picture is allocated by the decoder. no need to
free it */
snprintf(buf, sizeof(buf), outfilename, frame);
pgm_save(picture->data[0], picture->linesize[0],
c->width, c->height, buf);
frame++;
}
fclose(f);
avcodec_close(c);
av_free(c);
av_free(picture);
printf("\n");
}
int main(int argc, char **argv)
{
const char *filename;
/* must be called before using avcodec lib */
avcodec_init();
/* register all the codecs */
avcodec_register_all();
if (argc <= 1)
{
video_encode_example("asdf.mpg");
filename = "asdf.mpg";
}
else
{
filename = argv[1];
}
video_decode_example("%d.pgm", filename);
return 0;
}I tried with PIX_FMT_RGB24 and changing each channel accordingly. For this, I declared another :
AVFrame *pictureRGB ; and then : pictureRGB = avcodec_alloc_frame() ;
for(y=0; y < c->height; y++)
{
for(x=0; x < c->width; x++)
{
pictureRGB ->data[0][y * pictureRGB ->linesize[0] + x] = x + y + i * 3;
pictureRGB ->data[1][y * pictureRGB ->linesize[1] + x] = x + y + i * 3;
pictureRGB ->data[2][y * pictureRGB ->linesize[2] + x] = x + y + i * 3;
}
}But it gives errors ! I am totally new to this library. Is it possible to directly encode as a RGB dummy image rather than as YUV420P. Anybody out there with sound knowledge in this area ??? Thanks in advance !
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