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Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
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 (...) -
Support audio et vidéo HTML5
10 avril 2011MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)
Sur d’autres sites (9912)
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File Decryption in (AESMode.ctr) mode showing Exception Failed to decode data using encoding 'utf-8' in dart ?
20 novembre 2020, par JaiWhile decoding the video file using
aes-ctrmode am getting error like below,

Unhandled Exception: FileSystemException: Failed to decode data using encoding 'utf-8'

Used ffmpeg for encrypting file :


ffmpeg -i samplevideo.mp4 -vcodec copy -acodec copy -encryption_scheme cenc-aes-ctr -encryption_key 76a6c65c5ea762046bd749a2e632ccbb -encryption_kid a7e61c373e219033c21091fa607bf3b8 enc_v1_file.mp4

Used Dart to decode video file :


Future<string> decryptFile(filePath) async {
 // filePath - Local encrypted file path
 var encodedKey = 'NzZhNmM2NWM1ZWE3NjIwNDZiZDc0OWEyZTYzMmNjYmI=';
 var encodedIv = 'YTdlNjFjMzczZTIxOTAzM2MyMTA5MWZhNjA3YmYzYjg=';
 var encryptedBase64EncodedString = new File(filePath).readAsStringSync();
 var decoded = base64.decode(encryptedBase64EncodedString); // Error in this line
 final key1 = enc.Key.fromBase64(encodedKey);
 final iv = enc.IV.fromBase64(encodedIv);
 final encrypter = enc.Encrypter(enc.AES(key1, mode: enc.AESMode.ctr));
 final decrypted = encrypter.decryptBytes(enc.Encrypted(decoded), iv: iv);
 final filename = '${p.basenameWithoutExtension(filePath)}.mp4';
 final directoryName = p.dirname(filePath);
 final newFilePath = p.join(directoryName, filename);
 var newFile = new File(newFilePath);
 await newFile.writeAsBytes(decrypted);
 return newFilePath;
}
</string>

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Adding Text to Video with ffmpeg in Flutter
9 mars 2024, par AimanI am trying to add text to a video using ffmpeg package but it returns an error i.e. Return Code 1
Here's my code.


final videoPath = _controller.file.path;
 final outputName = videoPath.hashCode.toString();

 final output =
 File('${(await getTemporaryDirectory()).path}/$outputName.mp4');

 String command =
 "-y -i $videoPath -filter_complex '[0]scale=540:-1[s];[s]drawtext=fontfile=/storage/emulated/0/Download/SuperDessert.ttf:text='MY_TEXT':fontsize=24:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2' ${output.path}";

 final session = await FFmpegKit.execute(command);

 final returnCode = await session.getReturnCode();

 if (ReturnCode.isSuccess(returnCode)) {
 log("Success full text added");
 } else {
 log("Error adding text: ${await session.getFailStackTrace()}");
 }


I have tried changing the output directory, changed
fontfiletofont

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save a serial of images(cv::Mat) to a mp4 file in Variable Frame Rate mode by using ffmpeg library, how to set the pts ?
2 mai 2023, par ollydbg23In C++ code, I can correctly save a serial of images(opencv's
cv::Mat) to a mp4 file by usingffmpeglibrary, see the question and answer here : avformat_write_header() function call crashed when I try to save several RGB data to a output.mp4 file

Now here comes another question :


Rotem' answer in that question can have the
output.mp4saved correctly. When play the mp4 file, I see the frames(OpenCV'scv::Matimage) shows in a const rate.

What I can do if I have got the frames not in a const frequency, for example, the I got the first frame at the
0ms, and the second frame at the50msthe third frame at75ms, so that the each frame as associated time stamp, for example, those time stamp array are something like below :

int timestamp[100] = {0, 50, 75, ...};


What is the method to modify the Rotem's answer to reflect this ? It looks like I have to change the
ptsfield of eachframe. Because I just test the code, if I change this :

yuvFrame->pts = av_rescale_q(frame_count*frame_count, outCodecCtx->time_base, outStream->time_base); //Set PTS timestamp

// note I change from frame_count to frame_count*frame_count


Then the
output.mp4plays slower and slower, because the later frame has largeptsvalues.

Thanks.


EDIT


This is the code I'm currently used :


#include <iostream>
#include <vector>
#include <cstring>
#include <fstream>
#include <sstream>
#include <stdexcept>
#include <opencv2></opencv2>opencv.hpp>
extern "C" {
#include <libavutil></libavutil>imgutils.h>
#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>opt.h>
}

#include<cstdlib> // to generate time stamps

using namespace std;
using namespace cv;

int main()
{
 // Set up input frames as BGR byte arrays
 vector<mat> frames;

 int width = 640;
 int height = 480;
 int num_frames = 100;
 Scalar black(0, 0, 0);
 Scalar white(255, 255, 255);
 int font = FONT_HERSHEY_SIMPLEX;
 double font_scale = 1.0;
 int thickness = 2;

 for (int i = 0; i < num_frames; i++) {
 Mat frame = Mat::zeros(height, width, CV_8UC3);
 putText(frame, std::to_string(i), Point(width / 2 - 50, height / 2), font, font_scale, white, thickness);
 frames.push_back(frame);
 }

 // generate a serial of time stamps which is used to set the PTS value
 // suppose they are in ms unit, the time interval is between 30ms to 59ms
 vector<int> timestamps;

 for (int i = 0; i < num_frames; i++) {
 int timestamp;
 if (i == 0)
 timestamp = 0;
 else
 {
 int random = 30 + (rand() % 30);
 timestamp = timestamps[i-0] + random;
 }

 timestamps.push_back(timestamp);
 }

 // Populate frames with BGR byte arrays

 // Initialize FFmpeg
 //av_register_all();

 // Set up output file
 AVFormatContext* outFormatCtx = nullptr;
 //AVCodec* outCodec = nullptr;
 AVCodecContext* outCodecCtx = nullptr;
 //AVStream* outStream = nullptr;
 //AVPacket outPacket;

 const char* outFile = "output.mp4";
 int outWidth = frames[0].cols;
 int outHeight = frames[0].rows;
 int fps = 25;

 // Open the output file context
 avformat_alloc_output_context2(&outFormatCtx, nullptr, nullptr, outFile);
 if (!outFormatCtx) {
 cerr << "Error: Could not allocate output format context" << endl;
 return -1;
 }

 // Open the output file
 if (avio_open(&outFormatCtx->pb, outFile, AVIO_FLAG_WRITE) < 0) {
 cerr << "Error opening output file" << std::endl;
 return -1;
 }

 // Set up output codec
 const AVCodec* outCodec = avcodec_find_encoder(AV_CODEC_ID_H264);
 if (!outCodec) {
 cerr << "Error: Could not find H.264 codec" << endl;
 return -1;
 }

 outCodecCtx = avcodec_alloc_context3(outCodec);
 if (!outCodecCtx) {
 cerr << "Error: Could not allocate output codec context" << endl;
 return -1;
 }
 outCodecCtx->codec_id = AV_CODEC_ID_H264;
 outCodecCtx->codec_type = AVMEDIA_TYPE_VIDEO;
 outCodecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
 outCodecCtx->width = outWidth;
 outCodecCtx->height = outHeight;
 outCodecCtx->time_base = { 1, fps*1000 }; // 25000
 outCodecCtx->framerate = {fps, 1}; // 25
 outCodecCtx->bit_rate = 4000000;

 //https://github.com/leandromoreira/ffmpeg-libav-tutorial
 //We set the flag AV_CODEC_FLAG_GLOBAL_HEADER which tells the encoder that it can use the global headers.
 if (outFormatCtx->oformat->flags & AVFMT_GLOBALHEADER)
 {
 outCodecCtx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER; //
 }

 // Open output codec
 if (avcodec_open2(outCodecCtx, outCodec, nullptr) < 0) {
 cerr << "Error: Could not open output codec" << endl;
 return -1;
 }

 // Create output stream
 AVStream* outStream = avformat_new_stream(outFormatCtx, outCodec);
 if (!outStream) {
 cerr << "Error: Could not allocate output stream" << endl;
 return -1;
 }

 // Configure output stream parameters (e.g., time base, codec parameters, etc.)
 // ...

 // Connect output stream to format context
 outStream->codecpar->codec_id = outCodecCtx->codec_id;
 outStream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 outStream->codecpar->width = outCodecCtx->width;
 outStream->codecpar->height = outCodecCtx->height;
 outStream->codecpar->format = outCodecCtx->pix_fmt;
 outStream->time_base = outCodecCtx->time_base;

 int ret = avcodec_parameters_from_context(outStream->codecpar, outCodecCtx);
 if (ret < 0) {
 cerr << "Error: Could not copy codec parameters to output stream" << endl;
 return -1;
 }

 outStream->avg_frame_rate = outCodecCtx->framerate;
 //outStream->id = outFormatCtx->nb_streams++; <--- We shouldn't modify outStream->id

 ret = avformat_write_header(outFormatCtx, nullptr);
 if (ret < 0) {
 cerr << "Error: Could not write output header" << endl;
 return -1;
 }

 // Convert frames to YUV format and write to output file
 int frame_count = -1;
 for (const auto& frame : frames) {
 frame_count++;
 AVFrame* yuvFrame = av_frame_alloc();
 if (!yuvFrame) {
 cerr << "Error: Could not allocate YUV frame" << endl;
 return -1;
 }
 av_image_alloc(yuvFrame->data, yuvFrame->linesize, outWidth, outHeight, AV_PIX_FMT_YUV420P, 32);

 yuvFrame->width = outWidth;
 yuvFrame->height = outHeight;
 yuvFrame->format = AV_PIX_FMT_YUV420P;

 // Convert BGR frame to YUV format
 Mat yuvMat;
 cvtColor(frame, yuvMat, COLOR_BGR2YUV_I420);
 memcpy(yuvFrame->data[0], yuvMat.data, outWidth * outHeight);
 memcpy(yuvFrame->data[1], yuvMat.data + outWidth * outHeight, outWidth * outHeight / 4);
 memcpy(yuvFrame->data[2], yuvMat.data + outWidth * outHeight * 5 / 4, outWidth * outHeight / 4);

 // Set up output packet
 //av_init_packet(&outPacket); //error C4996: 'av_init_packet': was declared deprecated
 AVPacket* outPacket = av_packet_alloc();
 memset(outPacket, 0, sizeof(outPacket)); //Use memset instead of av_init_packet (probably unnecessary).
 //outPacket->data = nullptr;
 //outPacket->size = 0;

 yuvFrame->pts = av_rescale_q(timestamps[frame_count], outCodecCtx->time_base, outStream->time_base); //Set PTS timestamp

 // Encode frame and write to output file
 int ret = avcodec_send_frame(outCodecCtx, yuvFrame);
 if (ret < 0) {
 cerr << "Error: Could not send frame to output codec" << endl;
 return -1;
 }
 while (ret >= 0) {
 ret = avcodec_receive_packet(outCodecCtx, outPacket);
 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
 break;
 } else if (ret < 0) {
 cerr << "Error: Could not receive packet from output codec" << endl;
 return -1;
 }

 //av_packet_rescale_ts(&outPacket, outCodecCtx->time_base, outStream->time_base);

 outPacket->stream_index = outStream->index;

 outPacket->duration = av_rescale_q(1, outCodecCtx->time_base, outStream->time_base); // Set packet duration

 ret = av_interleaved_write_frame(outFormatCtx, outPacket);
 av_packet_unref(outPacket);
 if (ret < 0) {
 cerr << "Error: Could not write packet to output file" << endl;
 return -1;
 }
 }

 av_frame_free(&yuvFrame);
 }

 // Flush the encoder
 ret = avcodec_send_frame(outCodecCtx, nullptr);
 if (ret < 0) {
 std::cerr << "Error flushing encoder: " << std::endl;
 return -1;
 }

 while (ret >= 0) {
 AVPacket* pkt = av_packet_alloc();
 if (!pkt) {
 std::cerr << "Error allocating packet" << std::endl;
 return -1;
 }
 ret = avcodec_receive_packet(outCodecCtx, pkt);

 // Write the packet to the output file
 if (ret == 0)
 {
 pkt->stream_index = outStream->index;
 pkt->duration = av_rescale_q(1, outCodecCtx->time_base, outStream->time_base); // <---- Set packet duration
 ret = av_interleaved_write_frame(outFormatCtx, pkt);
 av_packet_unref(pkt);
 if (ret < 0) {
 std::cerr << "Error writing packet to output file: " << std::endl;
 return -1;
 }
 }
 }


 // Write output trailer
 av_write_trailer(outFormatCtx);

 // Clean up
 avcodec_close(outCodecCtx);
 avcodec_free_context(&outCodecCtx);
 avformat_free_context(outFormatCtx);

 return 0;
}
</int></mat></cstdlib></stdexcept></sstream></fstream></cstring></vector></iostream>

Especially, I have those changes to the original Rotem's answer :


Fist, I have some code to generate a time stamp array :


// generate a serial of time stamps which is used to set the PTS value
 // suppose they are in ms unit, the time interval is between 30ms to 59ms
 vector<int> timestamps;

 for (int i = 0; i < num_frames; i++) {
 int timestamp;
 if (i == 0)
 timestamp = 0;
 else
 {
 int random = 30 + (rand() % 30);
 timestamp = timestamps[i-0] + random;
 }

 timestamps.push_back(timestamp);
 }
</int>

Second, I just set the PTS by those values :


yuvFrame->pts = av_rescale_q(timestamps[frame_count], outCodecCtx->time_base, outStream->time_base); //Set PTS timestamp


Note that I have set the fps like below :


outCodecCtx->time_base = { 1, fps*1000 }; // 25000
 outCodecCtx->framerate = {fps, 1}; // 25


Now, when I run the program, I got a lot of warnings in the console :


[libx264 @ 0000022e7fa621c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0000022e7fa621c0] profile High, level 3.0, 4:2:0, 8-bit
[libx264 @ 0000022e7fa621c0] 264 - core 164 r3094M bfc87b7 - H.264/MPEG-4 AVC codec - Copyleft 2003-2022 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=4000 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] non-strictly-monotonic PTS
[libx264 @ 0000022e7fa621c0] invalid DTS: PTS is less than DTS
[mp4 @ 0000022e090b2300] pts (592) < dts (1129348497) in stream 0
Error: Could not write packet to output file


Any ideas ?
Thanks.


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