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Video d’abeille en portrait
14 mai 2011, par
Mis à jour : Février 2012
Langue : français
Type : Video
Autres articles (96)
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Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur
8 février 2011, parLa visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
Configuration de la boite multimédia
Dès (...) -
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
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27 avril 2010, parMediaspip core
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Sur d’autres sites (9420)
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ffmpeg : cannot save HLS stream to MKV
15 juillet 2021, par MasterAlerI am trying to achieve something straightforward : writing the code that captures a video stream and saves it into an *.mkv file "as-is" (yeah, no demuxing or reencoding or whatever). Just want to store those
AVPacket-s and the MKV container looks ready for that.

Note that the question is about ffmpeg library usage, the ffmpeg binary works fine and can be used to save the HLS steam data via the following :

ffmpeg -i https://bitdash-a.akamaihd.net/content/sintel/hls/playlist.m3u8 -c:v copy out.ts

I know that but the goal is to save any (or almost any) stream, thus the MKV. Actually, there is some code that already can save the streams' data, it fails specifically when trying it with HLS.

After some efforts to provide a short but readable MCVE, here's a sample code that reproduces the problem. The focus is on making the output codec work with HLS streams, thus it may lack a lot of things and details, like extra error checks, corner-cases, optimizations, proper timestamp handling, etc.


#include <atomic>
#include 
#include <deque>
#include <functional>
#include <iostream>
#include <memory>
#include <mutex>
#include <thread>

extern "C" {
#include "libavcodec/avcodec.h"
#include "libavfilter/avfilter.h"
#include "libavfilter/buffersink.h"
#include "libavfilter/buffersrc.h"
#include <libavcodec></libavcodec>avcodec.h>
#include <libavdevice></libavdevice>avdevice.h>
#include <libavformat></libavformat>avformat.h>
#include <libswscale></libswscale>swscale.h>
}

// Some public stream. The code works with RTSP, RTMP, MJPEG, etc.
// static const char SOURCE_NAME[] = "http://81.83.10.9:8001/mjpg/video.mjpg"; // works!

// My goal was an actual cam streaming via HLS, but here are some random HLS streams
// that reproduce the problem quite well. Playlists may differ, but the error is exactly the same
static const char SOURCE_NAME[] = "http://qthttp.apple.com.edgesuite.net/1010qwoeiuryfg/sl.m3u8"; // fails!
// static const char SOURCE_NAME[] = "https://bitdash-a.akamaihd.net/content/MI201109210084_1/m3u8s/f08e80da-bf1d-4e3d-8899-f0f6155f6efa.m3u8"; // fails!

using Pkt = std::unique_ptr;
std::deque<pkt> frame_buffer;
std::mutex frame_mtx;
std::condition_variable frame_cv;
std::atomic_bool keep_running{true};

AVCodecParameters *common_codecpar = nullptr;
std::mutex codecpar_mtx;
std::condition_variable codecpar_cv;

void read_frames_from_source(unsigned N)
{
 AVFormatContext *fmt_ctx = avformat_alloc_context();

 int err = avformat_open_input(&fmt_ctx, SOURCE_NAME, nullptr, nullptr);
 if (err < 0) {
 std::cerr << "cannot open input" << std::endl;
 avformat_free_context(fmt_ctx);
 return;
 }

 err = avformat_find_stream_info(fmt_ctx, nullptr);
 if (err < 0) {
 std::cerr << "cannot find stream info" << std::endl;
 avformat_free_context(fmt_ctx);
 return;
 }

 // Simply finding the first video stream, preferrably H.264. Others are ignored below
 int video_stream_id = -1;
 for (unsigned i = 0; i < fmt_ctx->nb_streams; i++) {
 auto *c = fmt_ctx->streams[i]->codecpar;
 if (c->codec_type == AVMEDIA_TYPE_VIDEO) {
 video_stream_id = i;
 if (c->codec_id == AV_CODEC_ID_H264)
 break;
 }
 }

 if (video_stream_id < 0) {
 std::cerr << "failed to find find video stream" << std::endl;
 avformat_free_context(fmt_ctx);
 return;
 }

 { // Here we have the codec params and can launch the writer
 std::lock_guard locker(codecpar_mtx);
 common_codecpar = fmt_ctx->streams[video_stream_id]->codecpar;
 }
 codecpar_cv.notify_all();

 unsigned cnt = 0;
 while (++cnt <= N) { // we read some limited number of frames
 Pkt pkt{av_packet_alloc(), [](AVPacket *p) { av_packet_free(&p); }};

 err = av_read_frame(fmt_ctx, pkt.get());
 if (err < 0) {
 std::cerr << "read packet error" << std::endl;
 continue;
 }

 // That's why the cycle above, we write only one video stream here
 if (pkt->stream_index != video_stream_id)
 continue;

 {
 std::lock_guard locker(frame_mtx);
 frame_buffer.push_back(std::move(pkt));
 }
 frame_cv.notify_one();
 }

 keep_running.store(false);
 avformat_free_context(fmt_ctx);
}

void write_frames_into_file(std::string filepath)
{
 AVFormatContext *out_ctx = nullptr;
 int err = avformat_alloc_output_context2(&out_ctx, nullptr, "matroska", filepath.c_str());
 if (err < 0) {
 std::cerr << "avformat_alloc_output_context2 failed" << std::endl;
 return;
 }

 AVStream *video_stream = avformat_new_stream(out_ctx, avcodec_find_encoder(common_codecpar->codec_id)); // the proper way
 // AVStream *video_stream = avformat_new_stream(out_ctx, avcodec_find_encoder(AV_CODEC_ID_H264)); // forcing the H.264
 // ------>> HERE IS THE TROUBLE, NO CODEC WORKS WITH HLS <<------

 int video_stream_id = video_stream->index;

 err = avcodec_parameters_copy(video_stream->codecpar, common_codecpar);
 if (err < 0) {
 std::cerr << "avcodec_parameters_copy failed" << std::endl;
 }

 if (!(out_ctx->flags & AVFMT_NOFILE)) {
 err = avio_open(&out_ctx->pb, filepath.c_str(), AVIO_FLAG_WRITE);
 if (err < 0) {
 std::cerr << "avio_open fail" << std::endl;
 return;
 }
 }

 err = avformat_write_header(out_ctx, nullptr); // <<--- ERROR WITH HLS HERE
 if (err < 0) {
 std::cerr << "avformat_write_header failed" << std::endl;
 return; // here we go with hls
 }

 unsigned cnt = 0;
 while (true) {
 std::unique_lock locker(frame_mtx);
 frame_cv.wait(locker, [&] { return !frame_buffer.empty() || !keep_running; });

 if (!keep_running)
 break;

 Pkt pkt = std::move(frame_buffer.front());
 frame_buffer.pop_front();
 ++cnt;
 locker.unlock();

 pkt->stream_index = video_stream_id; // mandatory
 err = av_write_frame(out_ctx, pkt.get());
 if (err < 0) {
 std::cerr << "av_write_frame failed " << cnt << std::endl;
 } else if (cnt % 25 == 0) {
 std::cout << cnt << " OK" << std::endl;
 }
 }

 av_write_trailer(out_ctx);
 avformat_free_context(out_ctx);
}

int main()
{
 std::thread reader(std::bind(&read_frames_from_source, 1000));
 std::thread writer;

 // Writer wont start until reader's got AVCodecParameters
 // In this example it spares us from setting writer's params properly manually

 { // Waiting for codec params to be set
 std::unique_lock locker(codecpar_mtx);
 codecpar_cv.wait(locker, [&] { return common_codecpar != nullptr; });
 writer = std::thread(std::bind(&write_frames_into_file, "out.mkv"));
 }

 reader.join();
 keep_running.store(false);
 writer.join();

 return 0;
}

</pkt></thread></mutex></memory></iostream></functional></deque></atomic>

What happens here ? Simply put :


- 

- Two threads are spawned, one reads packets from source and stores them in a buffer
- The writer waits for the reader to get the
AVCodecParameters, so that you can see they are the same being used, almost no manual param setting here - The reader is supposed to read N packets and finish, then the writer follows him. That's how it works with RTSP, RTMP, MJPEG, etc.








What's the problem ? Once an HLS stream is tried, there goes the following error :




Tag [27][0][0][0] incompatible with output codec id '27' (H264)




After that
the writer segfaults on any write attempt via it's context (that isavformat_write_headerhere)avformat_write_headerfails with an error (see UPD2 below) and thus no successfull write operation is possible.

What's been tried :


- 

- Forcing arbitrary codecs (ex. :
AV_CODEC_ID_H264). No luck there. - Trying the
AV_CODEC_ID_MPEGTS. No way, it's documented as a "fake" codec for internal needs. - Switching some of the multiple options for input or output contexts, no luck there








I'm currenly confused a lot 'coz the error sounds like "Tag H264 is not compatible with codec H264". The ffmpeg logs look like the library managed to comprehend it's dealing with MPEG-TS being sent via HLS, reading is fine but writing into the chosen media container fails :


[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/540_1200000/hls/segment_0.ts' for reading
[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/540_1200000/hls/segment_1.ts' for reading
[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/720_2400000/hls/segment_0.ts' for reading
[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/720_2400000/hls/segment_1.ts' for reading
[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/1080_4800000/hls/segment_0.ts' for reading
[hls @ 0x7f94b0000900] Opening 'https://bitdash-a.akamaihd.net/content/MI201109210084_1/video/1080_4800000/hls/segment_1.ts' for reading
[hls @ 0x7f94b0000900] Could not find codec parameters for stream 0 (Audio: aac ([15][0][0][0] / 0x000F), 0 channels, 112 kb/s): unspecified sample rate
Consider increasing the value for the 'analyzeduration' and 'probesize' options
[matroska @ 0x7f94a8000900] Tag [27][0][0][0] incompatible with output codec id '27' (H264)
avformat_write_header failed
Segmentation fault (core dumped)


No hard googling helped, I'm a bit desperate.

Plz, share your ideas, would be grateful for any.

UPD


- 

ffmpeg -i https://bitdash-a.akamaihd.net/content/sintel/hls/playlist.m3u8 out.mkvworks fineffmpeg -i http://qthttp.apple.com.edgesuite.net/1010qwoeiuryfg/sl.m3u8 -c:v copy out.mkvalso works fine






... which means ffmpeg can do the trick and the desired result can be achieved


UPD2


It occured that the tag error can be suppressed via

out_ctx->strict_std_compliance = FF_COMPLIANCE_UNOFFICIAL;

I assume it's smth about spelling the "h264" properly in a string tag, doesn't look serious.

Also, after a closer look it occured that it's
av_write_framethat actually segfaults. No wonder — with HLS streamsavformat_write_headerfails and returns error :



Invalid data found when processing input




That still leaves me with no clues, where's the problem here =((


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I'm having problem encoding video using Laravel FFMPEG to save it to Minio storage
8 juillet 2022, par Ibrahim AhmadI am trying to convert video from .mp4 extension into HLS format (.m3u8) using Laravel FFMPEG.


FFMpeg::fromDisk('minio')
 ->open($videoFile)
 ->exportForHLS()
 ->onProgress(function ($percentage) use ($movie) {
 Cache::put('progress-' . $movie->id, $percentage);

 if($percentage >= 100) {
 Cache::forget('progress-' . $movie->id);
 }
 })
 ->toDisk('minio')
 ->addFormat($lowBitrate, function (HLSVideoFilters $filter) {
 $filter->resize(480, 360);
 })
 ->addFormat($midBitrate, function (HLSVideoFilters $filter) {
 $filter->resize(852, 480);
 })
 ->addFormat($highBitrate, function (HLSVideoFilters $filter) {
 $filter->resize(1920, 1080);
 })
 ->save($newFile);


I have a .mp4 video stored in Minio S3 storage, want to export to Minio S3 storage again. And I came up with this error


RecursiveDirectoryIterator::__construct(C:\Windows\Temp/52325dd01cfde90a\): Access is deni (code: 5)


What does the error message say ? But when I export the video file to local, it works totally fine. How do I solve this problem. Thanks.


Update :
The export process requires windows temporary folder, and I cleared the temporary folder, the problem is solved for now. This probably the temporary folder can't hold many files.


-
Is there a way to program the (Download) button to save a group of images as a one video ?
9 février 2024, par Lina Al-fawzanThis is my entire code. Its function is that everything the user writes or says will have images returned to him according to what he wrote/said, and the next image will be shown to him after he presses “close,” and he can save each image separately. I want to make a simple modification to it. First, instead of a close button, I want each image to be displayed for 3 seconds and the next one to be displayed, and so on... “all of them in one window”, and for the “download” button to be when the last image is displayed, and for them all to be saved in one video.


import 'package:flutter/material.dart';
import 'package:flutter/services.dart' show rootBundle;
import 'dart:convert';
import 'dart:typed_data';
import 'package:image_gallery_saver/image_gallery_saver.dart';
import 'package:speech_to_text/speech_to_text.dart' as stt;

void main() {
 runApp(MyApp());
}

class MyApp extends StatelessWidget {
 @override
 Widget build(BuildContext context) {
 return MaterialApp(
 home: MyHomePage(),
 );
 }
}

class MyHomePage extends StatefulWidget {
 @override
 _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<myhomepage> {
 TextEditingController _textEditingController = TextEditingController();
 late stt.SpeechToText _speech;
 bool _isListening = false;

 @override
 void initState() {
 super.initState();
 _speech = stt.SpeechToText();
 }

 void _listen() async {
 if (!_isListening) {
 bool available = await _speech.initialize(
 onStatus: (val) => print('onStatus: $val'),
 onError: (val) => print('onError: $val'),
 );
 if (available) {
 setState(() => _isListening = true);
 _speech.listen(
 onResult: (val) => setState(() {
 _textEditingController.text = val.recognizedWords;
 if (val.hasConfidenceRating && val.confidence > 0) {
 _showImages(val.recognizedWords);
 }
 }),
 );
 }
 } else {
 setState(() => _isListening = false);
 _speech.stop();
 }
 }

 @override
 Widget build(BuildContext context) {
 return Scaffold(
 appBar: AppBar(
 title: Text('Image Viewer'),
 ),
 body: Padding(
 padding: const EdgeInsets.all(16.0),
 child: Column(
 mainAxisAlignment: MainAxisAlignment.center,
 children: [
 TextField(
 controller: _textEditingController,
 decoration: const InputDecoration(
 labelText: 'Enter a word',
 ),
 ),
 SizedBox(height: 16.0),
 ElevatedButton(
 onPressed: () {
 String userInput = _textEditingController.text;
 _showImages(userInput);
 },
 child: Text('Show Images'),
 ),
 SizedBox(height: 16.0),
 ElevatedButton(
 onPressed: _listen,
 child: Text(_isListening ? 'Stop Listening' : 'Start Listening'),
 ),
 ],
 ),
 ),
 );
 }

Future<void> _showImages(String userInput) async {
 String directoryPath = 'assets/output_images/';
 print("User Input: $userInput");
 print("Directory Path: $directoryPath");

 List<string> assetFiles = await rootBundle
 .loadString('AssetManifest.json')
 .then((String manifestContent) {
 final Map manifestMap = json.decode(manifestContent);
 return manifestMap.keys
 .where((String key) => key.startsWith(directoryPath))
 .toList();
 });

 List<string> imageFiles = assetFiles.where((String assetPath) =>
 assetPath.toLowerCase().endsWith('.jpg') ||
 assetPath.toLowerCase().endsWith('.gif')).toList();

 List<string> words = userInput.split(' '); // Tokenize the sentence into words

 for (String word in words) {
 String wordImagePath = '$directoryPath$word.gif';

 if (imageFiles.contains(wordImagePath)) {
 await _showDialogWithImage(wordImagePath);
 } else {
 for (int i = 0; i < word.length; i++) {
 String letter = word[i];
 String letterImagePath = imageFiles.firstWhere(
 (assetPath) => assetPath.toLowerCase().endsWith('$letter.jpg'),
 orElse: () => '',
 );
 if (letterImagePath.isNotEmpty) {
 await _showDialogWithImage(letterImagePath);
 } else {
 print('No image found for $letter');
 }
 }
 }
 }
}

 

 Future<void> _showDialogWithImage(String imagePath) async {
 await showDialog<void>(
 context: context,
 builder: (BuildContext context) {
 return AlertDialog(
 content: Image.asset(imagePath),
 actions: [
 TextButton(
 onPressed: () {
 Navigator.of(context).pop();
 },
 child: Text('Close'),
 ),
 TextButton(
 onPressed: () async {
 await _downloadImage(imagePath);
 Navigator.of(context).pop();
 },
 child: Text('Download'),
 ),
 ],
 );
 },
 );
 }

 Future<void> _downloadImage(String assetPath) async {
 try {
 final ByteData data = await rootBundle.load(assetPath);
 final List<int> bytes = data.buffer.asUint8List();

 final result = await ImageGallerySaver.saveImage(Uint8List.fromList(bytes));

 if (result != null) {
 ScaffoldMessenger.of(context).showSnackBar(
 SnackBar(
 content: Text('Image saved to gallery.'),
 ),
 );
 } else {
 ScaffoldMessenger.of(context).showSnackBar(
 SnackBar(
 content: Text('Failed to save image to gallery.'),
 ),
 );
 }
 } catch (e) {
 print('Error downloading image: $e');
 }
 }
}

</int></void></void></void></string></string></string></void></myhomepage>

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