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MediaSPIP v0.2
21 juin 2013, parMediaSPIP 0.2 est la première version de MediaSPIP stable.
Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...) -
Organiser par catégorie
17 mai 2013, parDans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...) -
MediaSPIP version 0.1 Beta
16 avril 2011, parMediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)
Sur d’autres sites (9698)
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Have problems using FFMPEG to save RGB image sequence to .mp4
28 septembre 2021, par ClubsI render some images with OpenGL and need to compose them into a video file. Each of the images is a sequence of uint8_t values representing a sRGB color component (image array looks like ...rgbrgbrgb...)



I know very little about video processing and have no experience with ffmpeg libraries at all. I made a little test program using these sources as reference :



https://ffmpeg.org/doxygen/trunk/encode_video_8c-example.html



How to convert RGB from YUV420p for ffmpeg encoder ?



The test program is supposed to make a video about growing green vertical stripe. I'm just trying to figure out how to make a video using some source of raw RGB data.



Here is my code :



#include <iostream>
#include <vector>
#include <algorithm>

extern "C" {
 #include <libavcodec></libavcodec>avcodec.h>
 #include <libavutil></libavutil>opt.h>
 #include <libavutil></libavutil>imgutils.h>
 #include <libswscale></libswscale>swscale.h>
}

static void encode( AVCodecContext* enc_ctx,
 AVFrame* frame, AVPacket* pkt,
 FILE* outfile )
{
 int ret;
 ret = avcodec_send_frame(enc_ctx, frame);
 if (ret < 0) {
 std::cerr << "Error sending a frame for encoding\n";
 return;
 }
 while (ret >= 0) {
 ret = avcodec_receive_packet(enc_ctx, pkt);
 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
 return;
 else if (ret < 0) {
 fprintf(stderr, "Error during encoding\n");
 exit(1);
 }
 fwrite(pkt->data, 1, pkt->size, outfile);
 av_packet_unref(pkt);
 }
}

static constexpr int w = 1920, h = 1080;
static constexpr float fps = 20.f, time = 5.f;
static constexpr int nFrames = static_cast<int>(fps * time);
static std::vector imageRGB(w * h * 3, 0);

static void UpdateImageRGB()
{
 static int d = 50;
 imageRGB.assign(w * h * 3, 0);
 for (int i = 0; i < h; ++i)
 for ( int j = std::max(0, w / 2 - d);
 j < std::min(w, w / 2 + d);
 ++j )
 {
 imageRGB[(w * i + j) * 3 + 0] = 50;
 imageRGB[(w * i + j) * 3 + 1] = 200;
 imageRGB[(w * i + j) * 3 + 2] = 50;
 }
 d += 5;
}

int main()
{
 int ret = 0;
 auto filename = "test.mp4";

 auto codec = avcodec_find_encoder(AV_CODEC_ID_H264);
 if (!codec) {
 std::cerr << "Codec \"x.264\" not found\n";
 return 1;
 }
 auto c = avcodec_alloc_context3(codec);
 if (!c) {
 std::cerr << "Could not allocate video codec context\n";
 return 1;
 }
 auto pkt = av_packet_alloc();
 if (!pkt) return 1;

 // 1.8 bits / (pixel * frame)
 c->bit_rate = static_cast(1.8f * w * h * fps);
 /* resolution must be a multiple of two */
 c->width = w;
 c->height = h;
 /* frames per second */
 c->time_base = AVRational{ 1, static_cast<int>(fps) };
 c->framerate = AVRational{ static_cast<int>(fps), 1 };

 c->gop_size = 10;
 c->max_b_frames = 1;
 c->pix_fmt = AV_PIX_FMT_YUV420P;
 av_opt_set(c->priv_data, "preset", "slow", 0);
 av_opt_set(c->priv_data, "preset", "slow", 0);

 ret = avcodec_open2(c, codec, NULL);
 if (ret < 0) {
 char str[AV_ERROR_MAX_STRING_SIZE];
 std::cerr << "Could not open codec: "
 << av_make_error_string(str, AV_ERROR_MAX_STRING_SIZE, ret)
 << "\n";
 return 1;
 }

 FILE * f;
 fopen_s(&f, filename, "wb");
 if (!f) {
 std::cerr << "Could not open " << filename << '\n';
 return 1;
 }

 auto frame = av_frame_alloc();
 if (!frame) {
 std::cerr << "Could not allocate video frame\n";
 return 1;
 }
 frame->format = c->pix_fmt;
 frame->width = c->width;
 frame->height = c->height;
 ret = av_frame_get_buffer(frame, 0);
 if (ret < 0) {
 std::cerr << stderr, "Could not allocate the video frame data\n";
 return 1;
 }

 SwsContext* ctx = sws_getContext( w, h, AV_PIX_FMT_RGB24,
 w, h, AV_PIX_FMT_YUV420P,
 0, 0, 0, 0 );

 for (int i = 0; i < nFrames; i++)
 {
 ret = av_frame_make_writable(frame);
 UpdateImageRGB();
 static const uint8_t* rgbData[1] = { &imageRGB[0] };
 static constexpr int rgbLinesize[1] = { 3 * w };
 sws_scale( ctx, rgbData, rgbLinesize, 0, h,
 frame->data, frame->linesize );
 frame->pts = i;
 /* encode the image */
 encode(c, frame, pkt, f);
 }
 encode(c, NULL, pkt, f);

 fclose(f);
 avcodec_free_context(&c);
 av_frame_free(&frame);
 av_packet_free(&pkt);
 return 0;
}
</int></int></int></algorithm></vector></iostream>


The program generates 33.9k video file with further console output :



[libx264 @ 0000020c18681800] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0000020c18681800] profile High, level 5.0, 4:2:0, 8-bit
[libx264 @ 0000020c18681800] frame I:11 Avg QP: 0.00 size: 639
[libx264 @ 0000020c18681800] frame P:74 Avg QP: 0.32 size: 174
[libx264 @ 0000020c18681800] frame B:15 Avg QP: 2.26 size: 990
[libx264 @ 0000020c18681800] consecutive B-frames: 70.0% 30.0%
[libx264 @ 0000020c18681800] mb I I16..4: 100.0% 0.0% 0.0%
[libx264 @ 0000020c18681800] mb P I16..4: 0.6% 0.0% 0.0% P16..4: 2.1% 0.0% 0.0% 0.0% 0.0% skip:97.3%
[libx264 @ 0000020c18681800] mb B I16..4: 0.1% 0.0% 0.0% B16..8: 0.6% 0.0% 0.0% direct: 0.6% skip:98.7% L0:39.8% L1:60.2% BI: 0.0%
[libx264 @ 0000020c18681800] final ratefactor: -46.47
[libx264 @ 0000020c18681800] 8x8 transform intra:0.0%
[libx264 @ 0000020c18681800] direct mvs spatial:0.0% temporal:100.0%
[libx264 @ 0000020c18681800] coded y,uvDC,uvAC intra: 0.0% 0.1% 0.1% inter: 0.0% 0.1% 0.1%
[libx264 @ 0000020c18681800] i16 v,h,dc,p: 99% 0% 1% 0%
[libx264 @ 0000020c18681800] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 0% 0% 100% 0% 0% 0% 0% 0% 0%
[libx264 @ 0000020c18681800] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 46% 0% 54% 0% 0% 0% 0% 0% 0%
[libx264 @ 0000020c18681800] i8c dc,h,v,p: 96% 1% 3% 0%
[libx264 @ 0000020c18681800] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0000020c18681800] ref P L0: 70.2% 0.0% 29.8% 0.0% 0.0%
[libx264 @ 0000020c18681800] kb/s:55.61



- 

- "Media Player Classic" on Windows plays this video but the time slider doesn't move, and the video cannot be fast-forwarded to some frame
- VLC cannot play the video at all. It launches, shows me VLC logo, and time slider (which is unusually big) jumps from left to right, not responding to my clicks
- If I set time = 0.05 to make a video of only 1 frame, I cannot play it even with "Media Player Classic". I want to make an algorithm to convert the arbitrary number of raw RGB images into the video files, even if there's only one image, and with arbitrary image size (that is, width and height may be odd).
- As I said, I don't really understand what am I doing. There are low-level codec settings in lines 83-84. Are they all right ?
- Do I have to manually set a bit rate (line 75) ? Shouldn't it be calculated automatically by the codec ?












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extract audio using ffmpeg and save wav files
7 mai 2018, par jameshwart lopezffmpeg has a way to extract video images using the following command
ffmpeg -i "video.avi" -vf fps=30 "images/frame_%09d.png" -hide_bannerIs there a way in ffmpeg to extract or cut audios into smaller chunks the same way that is done on the above command but the difference is it will create an audio file not an image file.
I tried the following but it only creates a wav file.
ffmpeg -i "video.avi" -vf fps=30 "images/frame_%09d.wav" -hide_banner -
How to save sequence of images in `000` pattern [on hold]
17 mars 2014, par Maged E Williami try to make video out of images, but i only know how to do that with one image like this :
ffmpeg -f image2 -i C:\Secret\17_03_2014_11_31_34_AM\000.jpeg -r 12 -s 683x384 C:\Secret\17_03_2014_11_31_34_AM\foo.avinow here's my images looks like :
i tried this :
ffmpeg -f image2 -i C:\Secret\17_03_2014_11_31_34_AM\-%03d.jpeg -r 12 -s 683x384 C:\Secret\17_03_2014_11_31_34_AM\foo.avibut it says :
could find no file with path 'C:\Secret\17_03_2014_11_31_34_AM\-%03d.jpeg' and index in the range 0-4
C:\Secret\17_03_2014_11_31_34_AM\-%03d.jpeg: no such file directory
>any help with converting all of them ?
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