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Autres articles (111)
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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. -
Script d’installation automatique de MediaSPIP
25 avril 2011, parAfin de palier aux difficultés d’installation dues principalement aux dépendances logicielles coté serveur, un script d’installation "tout en un" en bash a été créé afin de faciliter cette étape sur un serveur doté d’une distribution Linux compatible.
Vous devez bénéficier d’un accès SSH à votre serveur et d’un compte "root" afin de l’utiliser, ce qui permettra d’installer les dépendances. Contactez votre hébergeur si vous ne disposez pas de cela.
La documentation de l’utilisation du script d’installation (...) -
Support de tous types de médias
10 avril 2011Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)
Sur d’autres sites (11137)
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Creating GIF from QImages with ffmpeg
21 mars 2020, par SierraI would like to generate GIF from QImage, using ffmpeg - all of that programmatically (C++). I’m working with Qt 5.6 and the last build of ffmpeg (build git-0a9e781 (2016-06-10).
I’m already able to convert these QImage in .mp4 and it works. I tried to use the same principle for the GIF, changing format pixel and codec. GIF is generated with two pictures (1 second each), in 15 FPS.
## INITIALIZATION
#####################################################################
// Filepath : "C:/Users/.../qt_temp.Jv7868.gif"
// Allocating an AVFormatContext for an output format...
avformat_alloc_output_context2(formatContext, NULL, NULL, filepath);
...
// Adding the video streams using the default format codecs and initializing the codecs.
stream = avformat_new_stream(formatContext, *codec);
AVCodecContext * codecContext = avcodec_alloc_context3(*codec);
context->codec_id = codecId;
context->bit_rate = 400000;
...
context->pix_fmt = AV_PIX_FMT_BGR8;
...
// Opening the codec...
avcodec_open2(codecContext, codec, NULL);
...
frame = allocPicture(codecContext->width, codecContext->height, codecContext->pix_fmt);
tmpFrame = allocPicture(codecContext->width, codecContext->height, AV_PIX_FMT_RGBA);
...
avformat_write_header(formatContext, NULL);
## ADDING A NEW FRAME
#####################################################################
// Getting in parameter the QImage: newFrame(const QImage & image)
const qint32 width = image.width();
const qint32 height = image.height();
// Converting QImage into AVFrame
for (qint32 y = 0; y < height; y++) {
const uint8_t * scanline = image.scanLine(y);
for (qint32 x = 0; x < width * 4; x++) {
tmpFrame->data[0][y * tmpFrame->linesize[0] + x] = scanline[x];
}
}
...
// Scaling...
if (codec->pix_fmt != AV_PIX_FMT_BGRA) {
if (!swsCtx) {
swsCtx = sws_getContext(codec->width, codec->height,
AV_PIX_FMT_BGRA,
codec->width, codec->height,
codec->pix_fmt,
SWS_BICUBIC, NULL, NULL, NULL);
}
sws_scale(swsCtx,
(const uint8_t * const *)tmpFrame->data,
tmpFrame->linesize,
0,
codec->height,
frame->data,
frame->linesize);
}
frame->pts = nextPts++;
...
int gotPacket = 0;
AVPacket packet = {0};
av_init_packet(&packet);
avcodec_encode_video2(codec, &packet, frame, &gotPacket);
if (gotPacket) {
av_packet_rescale_ts(paket, *codec->time_base, stream->time_base);
paket->stream_index = stream->index;
av_interleaved_write_frame(formatContext, paket);
}But when I’m trying to modify the video codec and pixel format to match with GIF specifications, I’m facing some issues.
I tried several codecs such asAV_CODEC_ID_GIF
andAV_CODEC_ID_RAWVIDEO
but none of them seem to work. During the initialization phase,avcodec_open2()
always returns such kind of errors :Specified pixel format rgb24 is invalid or not supported
Could not open video codec: gifEDIT 17/06/2016
Digging a little bit more,
avcodec_open2()
returns -22 :#define EINVAL 22 /* Invalid argument */
EDIT 22/06/2016
Here are the flags used to compile ffmpeg :
"FFmpeg/Libav configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --disable-w32threads --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib"
Did I miss a crucial one for GIF ?
EDIT 27/06/2016
Thanks to Gwen, I have a first output : I setted the
context->pix_fmt
toAV_PIX_FMT_BGR8
. Btw I’m still facing some issues with the generated GIF. It’s not playing and encoding appears to fail.GIF generated in command lines with ffmpeg (left) . . . GIF generated programmatically (right)
It looks like some options are not defined... also may be a wrong conversion between QImage and AVFrame ? I updated the code above. It represents a lot of code, so I tried to stay short. Don’t hesitate to ask more details.
End of EDIT
I’m not really familiar with ffmpeg, any kind of help would be highly appreciated. Thank you.
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Interlaced (1080i) video converted to deinterlaced (1080p) won't play in Quicktime or other players, except VLC
24 avril 2020, par cozmonautI'm trying to convert a 1080i ts video clip to 1080p mp4. I've found many different ffmpeg commands to do this, which all successfully convert to 1080p mp4, however, none of generated clips will open in Quicktime or any another other player, other than VLC. I've read about the need to have the correct color space (i.e. yuv420p) for Quicktime to work, and also that 10 bit files won't work (only 8 bit). However, when these things have been accounted for, the resulting video clips still won't open in Quicktime.






Here are the commands I've tried.



ffmpeg -i test_original_interlaced.ts -vf bwdif -c:v libx264 -preset slow -crf 18 -pix_fmt yuv420p -c:a aac -b:a 320k test_generated_progressive.mp4

 ffmpeg -i test_original_interlaced.ts -vf yadif -c:v libx264 -preset slow -crf 19 -c:a aac -b:a 256k test_generated_progressive.mp4

 ffmpeg -i test_original_interlaced.ts -vf yadif -c:v libx264 -preset slow -crf 18 -pix_fmt yuv420p -c:a aac -b:a 256k test_generated_progressive.mp4

 ffmpeg -i test_original_interlaced.ts -vf yadif=parity=auto test_generated_progressive.mp4







Here are the 1080i ts details and link to the original video clip :



ffmpeg version 4.2.1-tessus https://evermeet.cx/ffmpeg/ Copyright (c) 2000-2019 the FFmpeg developers
 built with Apple LLVM version 10.0.1 (clang-1001.0.46.4)
 configuration: --cc=/usr/bin/clang --prefix=/opt/ffmpeg --extra-version=tessus --enable-avisynth --enable-fontconfig --enable-gpl --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libmysofa --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvmaf --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-version3 --pkg-config-flags=--static --disable-ffplay
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
Input #0, mpegts, from '/Users/test_original_interlaced.ts':
 Duration: 00:00:05.26, start: 1.400000, bitrate: 15183 kb/s
 Program 1 
 Metadata:
 service_name : Service01
 service_provider: FFmpeg
 Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv, top first), 1920x1080 [SAR 1:1 DAR 16:9], Closed Captions, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
 Stream #0:1[0x101](eng): Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz, 5.1(side), fltp, 384 kb/s




Link to original video clip (10 MB) : https://www.dropbox.com/s/85tv3v91lflfpon/test_original_interlaced.ts?dl=0






Here are the 1080p mp4 details and link to the generated video clip (that won't open in Quicktime) :



ffmpeg version 4.2.1-tessus https://evermeet.cx/ffmpeg/ Copyright (c) 2000-2019 the FFmpeg developers
 built with Apple LLVM version 10.0.1 (clang-1001.0.46.4)
 configuration: --cc=/usr/bin/clang --prefix=/opt/ffmpeg --extra-version=tessus --enable-avisynth --enable-fontconfig --enable-gpl --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libmysofa --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvmaf --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-version3 --pkg-config-flags=--static --disable-ffplay
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
Guessed Channel Layout for Input Stream #0.1 : 5.1
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/test_generated_progressive.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf58.29.100
 Duration: 00:00:05.27, start: 0.000000, bitrate: 9873 kb/s
 Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], Closed Captions, 9543 kb/s, 59.94 fps, 59.94 tbr, 60k tbn, 119.88 tbc (default)
 Metadata:
 handler_name : VideoHandler
 Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 5.1, fltp, 319 kb/s (default)
 Metadata:
 handler_name : SoundHandler




Link to generated video clip (6.5 MB) : https://www.dropbox.com/s/w744mdee5drvmya/test_generated_progressive.mp4?dl=0






Any help would be greatly appreciated.



Thank you.


-
Unable to encode H264 video using FFMPEG example
4 mai 2020, par Basit AnwerFFMPEG encode example fails to create a H264 video. MPEG1 works fine though.



Pasting the code here as well




 * @file
 * video encoding with libavcodec API example
 *
 * @example encode_video.c
 */
 #include 
 #include 
 #include 
 #include <libavcodec></libavcodec>avcodec.h>
 #include <libavutil></libavutil>opt.h>
 #include <libavutil></libavutil>imgutils.h>
 static void encode(AVCodecContext *enc_ctx, AVFrame *frame, AVPacket *pkt,
 FILE *outfile)
 {
 int ret;
 /* send the frame to the encoder */
 if (frame)
 printf("Send frame %3"PRId64"\n", frame->pts);
 ret = avcodec_send_frame(enc_ctx, frame);
 if (ret < 0) {
 fprintf(stderr, "Error sending a frame for encoding\n");
 exit(1);
 }
 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);
 }
 printf("Write packet %3"PRId64" (size=%5d)\n", pkt->pts, pkt->size);
 fwrite(pkt->data, 1, pkt->size, outfile);
 av_packet_unref(pkt);
 }
 }

 int main(int argc, char **argv)
 {
 const char *filename, *codec_name;
 const AVCodec *codec;
 AVCodecContext *c= NULL;
 int i, ret, x, y;
 FILE *f;
 AVFrame *frame;
 AVPacket *pkt;
 uint8_t endcode[] = { 0, 0, 1, 0xb7 };
 if (argc <= 2) {
 fprintf(stderr, "Usage: %s <output file="file"> <codec>\n", argv[0]);
 exit(0);
 }
 filename = argv[1];
 codec_name = argv[2];
 /* find the mpeg1video encoder */
 codec = avcodec_find_encoder_by_name(codec_name);
 if (!codec) {
 fprintf(stderr, "Codec '%s' not found\n", codec_name);
 exit(1);
 }
 c = avcodec_alloc_context3(codec);
 if (!c) {
 fprintf(stderr, "Could not allocate video codec context\n");
 exit(1);
 }
 pkt = av_packet_alloc();
 if (!pkt)
 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 = (AVRational){1, 25};
 c->framerate = (AVRational){25, 1};
 /* 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
 */
 c->gop_size = 10;
 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 */
 ret = avcodec_open2(c, codec, NULL);
 if (ret < 0) {
 fprintf(stderr, "Could not open codec: %s\n", av_err2str(ret));
 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;
 ret = av_frame_get_buffer(frame, 32);
 if (ret < 0) {
 fprintf(stderr, "Could not allocate the video frame data\n");
 exit(1);
 }
 /* encode 1 second of video */
 for (i = 0; i < 25; i++) {
 fflush(stdout);
 /* make sure the frame data is writable */
 ret = av_frame_make_writable(frame);
 if (ret < 0)
 exit(1);
 /* prepare a dummy image */
 /* Y */
 for (y = 0; y < c->height; y++) {
 for (x = 0; x < c->width; x++) {
 frame->data[0][y * frame->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++) {
 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 */
 encode(c, frame, pkt, f);
 }
 /* flush the encoder */
 encode(c, NULL, pkt, f);
 /* add sequence end code to have a real MPEG file */
 if (codec->id == AV_CODEC_ID_MPEG1VIDEO || codec->id == AV_CODEC_ID_MPEG2VIDEO)
 fwrite(endcode, 1, sizeof(endcode), f);
 fclose(f);
 avcodec_free_context(&c);
 av_frame_free(&frame);
 av_packet_free(&pkt);
 return 0;
 }
</codec></output>



The code fails at encode call and every
avcodec_receive_packet
call returnsAVERROR(EAGAIN)



What am i missing here ?