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Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...) -
XMP PHP
13 mai 2011, parDixit Wikipedia, XMP signifie :
Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...)
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Use FFmpeg to crop a video to square format in Android
22 août 2016, par Cédric PortmannI am currently working on an app that is supposed to crop a 16:9 video into a 1:1 video. However I dont get the code working. If possible the software should convert the inputed video as fast as possible. The resolution can vary between 480x480 and 720x720.
If I could choose the postion of the crop frame it would be perfect.
The error I get :
E/FFmpeg: Exception while trying to run: [Ljava.lang.String;@f0c91b8
java.io.IOException: Error running exec(). Command: [/data/user/0/com.android.grafika/files/ffmpeg, -i /storage/emulated/0/Alphacrypt1.mp4 -vf crop=640:256:0:400 -threads 5 -preset ultrafast -strict -2 /storage/emulated/0/YourCroppedMovie.mp4] Working Directory: null Environment: null
at java.lang.ProcessManager.exec(ProcessManager.java:215)
at java.lang.Runtime.exec(Runtime.java:174)
at java.lang.Runtime.exec(Runtime.java:129)
at com.github.hiteshsondhi88.libffmpeg.ShellCommand.run(ShellCommand.java:10)
at com.github.hiteshsondhi88.libffmpeg.FFmpegExecuteAsyncTask.doInBackground(FFmpegExecuteAsyncTask.java:38)
at com.github.hiteshsondhi88.libffmpeg.FFmpegExecuteAsyncTask.doInBackground(FFmpegExecuteAsyncTask.java:10)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.io.IOException: No such file or directory
at java.lang.ProcessManager.exec(Native Method)
at java.lang.ProcessManager.exec(ProcessManager.java:213)
at java.lang.Runtime.exec(Runtime.java:174)
at java.lang.Runtime.exec(Runtime.java:129)
at com.github.hiteshsondhi88.libffmpeg.ShellCommand.run(ShellCommand.java:10)
at com.github.hiteshsondhi88.libffmpeg.FFmpegExecuteAsyncTask.doInBackground(FFmpegExecuteAsyncTask.java:38)
at com.github.hiteshsondhi88.libffmpeg.FFmpegExecuteAsyncTask.doInBackground(FFmpegExecuteAsyncTask.java:10)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)The code I am using :
final String[] cmd = new String[]{"-i /storage/emulated/0/Alphacrypt1.mp4 -vf crop=640:256:0:400 -threads 5 -preset ultrafast -strict -2 /storage/emulated/0/YourCroppedMovie.mp4"};
try {
final FFmpeg ffmpeg = FFmpeg.getInstance(this);
ffmpeg.execute(cmd, new FFmpegExecuteResponseHandler() {
@Override
public void onSuccess(String message) {
Toast.makeText(getApplicationContext(), "Successfully converted!",
Toast.LENGTH_LONG).show();
}
@Override
public void onProgress(String message) {
}
@Override
public void onFailure(String message) {
Toast.makeText(getApplicationContext(), "Fail!"+ message,
Toast.LENGTH_LONG).show();
}
@Override
public void onStart() {
Toast.makeText(getApplicationContext(), "Started!",
Toast.LENGTH_LONG).show();
}
@Override
public void onFinish() {
Toast.makeText(getApplicationContext(), "Stopped!",
Toast.LENGTH_LONG).show();
}
});
} catch (FFmpegCommandAlreadyRunningException e) {
}Thank you for your help.
SOLUTION :
- I did not add the "Load Binary" part, which is necessary to run the
FFmpeg library (http://writingminds.github.io/ffmpeg-android-java/). - The command needs to be splitted using
.split(" ");as already told by printfmyname - For now I use -vf crop=1080:1080:0:0 to crop the video to a square. (Without messing up the ratio)
- I did not add the "Load Binary" part, which is necessary to run the
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Use ffmpeg to pan right over an image and then pan left to the original location
4 février 2024, par user1517922I'm using this command to pan to the right for 5 seconds on an image (like a 1080x1080 window moving across a larger image, 500px from the top) :


ffmpeg -loop 1 -r 30 -i image.jpg -vf crop=w=1080:h=1080:x=n:y=500 -frames:v 150 -pix_fmt yuv420p -preset fast -crf 30 video.mp4

I'd like to pan back to the left for 5 seconds to end up at the same spot.


The desired affect is when the video is on loop the square window pans right for 5 seconds then back left for 5 seconds then repeats, smooth and without flicker.


I suspect I need to use zoompan, but I haven't had success trying that.


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How to convert multiple jpg images to MP4 format using FFmpeg ?
30 janvier 2024, par PDLAOZEI- 

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I first used the FFmpeg command line to implement this function.

ffmpeg -framerate 1 -pattern_type glob -i "./image/*.jpg" -c:v libx264 -crf 25 -vf format=yuv420p -movflags +faststart test.mp4

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Then I use FFmpeg's api to convert multiple jpg into MP4 format, the process is probably.








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- Find the AV_CODEC_ID_MPEG4 encoder.
- Turn on the encoder.
- Set video stream parameters.
- Open the output file.
- Write file header.
- Allocate image frame rate and buffer.
- Write each jpg image to the video (write in a loop).
7-1. read jpg image.
7-2. Find video stream information.
7-3. Decoded image frame.
7-4. Transcode to yuv420p.
7-5. Encode and write video frames.
- Finally, free memory.


















update the reproducible example


#include <iostream>
#include <vector>
#include <string>
#include <chrono>
#include <thread>

#include <filesystem>
#include <algorithm>
#include <iomanip>
#include <sys></sys>stat.h>

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

namespace fs = std::filesystem;

bool compareFilenames(const std::string &str1, const std::string &str2)
{
 //ToDo Sort
}

int main()
{
 
 fs::path folderPath = "" //replace your image foldePath

 std::vector imageFiles;
 for (const auto &entry : fs::directory_iterator(folderPath))
 {
 if (entry.is_regular_file() && entry.path().extension() == ".jpg")
 {
 imageFiles.push_back(entry.path());
 }
 }

 std::sort(imageFiles.begin(), imageFiles.end(), compareFilenames);

 std::string outputVideoFile = "output.mp4";

 AVFormatContext *formatContext = nullptr;
 AVCodecContext *codecContext = nullptr;
 AVStream *videoStream = nullptr;

 av_register_all();
 avformat_alloc_output_context2(&formatContext, nullptr, nullptr, outputVideoFile.c_str());


 AVCodec *codec = avcodec_find_encoder(AV_CODEC_ID_MPEG4);//AV_CODEC_ID_H264
 videoStream = avformat_new_stream(formatContext, codec);
 codecContext = avcodec_alloc_context3(codec);

 codecContext->codec_id = codec->id;
 codecContext->codec_type = AVMEDIA_TYPE_VIDEO;
 codecContext->pix_fmt = AV_PIX_FMT_YUV420P;
 codecContext->width = 1920;
 codecContext->height = 1080;
 codecContext->time_base = {1, 2}; 
 codecContext->bit_rate = 100000000;
 codecContext->gop_size = 1;

 avcodec_open2(codecContext, codec, nullptr);
 avcodec_parameters_from_context(videoStream->codecpar, codecContext);

 avio_open(&formatContext->pb, outputVideoFile.c_str(), AVIO_FLAG_WRITE);
 avformat_write_header(formatContext, NULL);

 AVFrame *frame = av_frame_alloc();

 std::vector imageBuffer(codecContext->width * codecContext->height * 3);
 AVPacket packet;

 for (const std::string &imageFile : imageFiles)
 {

 AVFormatContext *inputFormatContext = avformat_alloc_context();
 avformat_open_input(&inputFormatContext, imageFile.c_str(), nullptr, nullptr);

 avformat_find_stream_info(inputFormatContext, nullptr);

 AVCodec *inputCodec = nullptr;
 AVCodecContext *inputCodecContext = nullptr;
 int videoStreamIndex = -1;

 for (unsigned int i = 0; i < inputFormatContext->nb_streams; i++)
 {
 if (inputFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
 {
 videoStreamIndex = i;
 inputCodec = avcodec_find_decoder(inputFormatContext->streams[i]->codecpar->codec_id);
 inputCodecContext = avcodec_alloc_context3(inputCodec);
 avcodec_parameters_to_context(inputCodecContext, inputFormatContext->streams[i]->codecpar);
 avcodec_open2(inputCodecContext, inputCodec, NULL);
 break;
 }
 }

 AVFrame *inputFrame = av_frame_alloc();
 while (av_read_frame(inputFormatContext, &packet) >= 0)
 {
 if (packet.stream_index == videoStreamIndex)
 {
 int response = avcodec_send_packet(inputCodecContext, &packet);

 while (response >= 0)
 {
 response = avcodec_receive_frame(inputCodecContext, inputFrame);
 if (response == AVERROR(EAGAIN) || response == AVERROR_EOF)
 {
 break;
 }
 else if (response < 0)
 {
 std::cerr << "Failed to receive frame from input decoder" << std::endl;
 break;
 }

 AVFrame *yuvFrame = av_frame_alloc();
 av_image_alloc(yuvFrame->data, yuvFrame->linesize, codecContext->width, codecContext->height, codecContext->pix_fmt, 1);

 SwsContext *yuvSwsContext = sws_getContext(inputFrame->width, inputFrame->height, AV_PIX_FMT_RGB24,
 codecContext->width, codecContext->height, codecContext->pix_fmt,
 0, nullptr, nullptr, nullptr);

 sws_scale(yuvSwsContext, inputFrame->data, inputFrame->linesize, 0, inputFrame->height,
 yuvFrame->data, yuvFrame->linesize);


 memcpy(imageBuffer.data(), yuvFrame->data[0], codecContext->width * codecContext->height);
 memcpy(imageBuffer.data() + codecContext->width * codecContext->height, yuvFrame->data[1], codecContext->width * codecContext->height / 4);
 memcpy(imageBuffer.data() + codecContext->width * codecContext->height * 5 / 4, yuvFrame->data[2], codecContext->width * codecContext->height / 4);

 frame->data[0] = imageBuffer.data();
 frame->data[1] = frame->data[0] + codecContext->width * codecContext->height;
 frame->data[2] = frame->data[1] + codecContext->width * codecContext->height / 4;
 frame->linesize[0] = codecContext->width;
 frame->linesize[1] = codecContext->width / 2;
 frame->linesize[2] = codecContext->width / 2;
 frame->width = codecContext->width;
 frame->height = codecContext->height;
 frame->format = codecContext->pix_fmt;
 frame->pts = av_rescale_q(videoStream->nb_frames, videoStream->time_base, videoStream->codec->time_base);

 av_init_packet(&packet);
 packet.data = nullptr;
 packet.size = 0;

 avcodec_send_frame(codecContext, frame);

 while (avcodec_receive_packet(codecContext, &packet) >= 0)
 {
 av_packet_rescale_ts(&packet, codecContext->time_base, videoStream->time_base);
 packet.stream_index = videoStream->index;

 av_write_frame(formatContext, &packet);
 av_packet_unref(&packet);
 }

 av_freep(&yuvFrame->data[0]);
 av_freep(&yuvFrame);
 sws_freeContext(yuvSwsContext);
 }
 }

 av_packet_unref(&packet);
 }

 av_frame_free(&inputFrame);
 avcodec_close(inputCodecContext);
 avformat_close_input(&inputFormatContext);
 }

 av_write_trailer(formatContext);

 av_frame_free(&frame);
 avcodec_close(codecContext);
 av_free(codecContext);
 avio_close(formatContext->pb);
 avformat_free_context(formatContext);

 return 0;
}


</iomanip></algorithm></filesystem></thread></chrono></string></vector></iostream>

But the encoding format is mpeg, which cannot be opened in the player included with windows, and the prompt is an unsupported format.


Although the vlc player can be opened and played normally, I need to play it normally on the player that comes with windows, because the output video will be played on the browser.


So I changed AV_CODEC_ID_MPEG4 to AV_CODEC_ID_H264, and the result is that although the file size of the output image is very large, only one picture is displayed during playback. I don't know what the problem is.


I was thinking about writing a new one, but I had no idea how to write a new one.
I would appreciate it if someone could write me an example.


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