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DJ Dolores - Oslodum 2004 (includes (cc) sample of “Oslodum” by Gilberto Gil)
15 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Audio
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Vous pouvez personnaliser le formulaire de création d’un éditorial.
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Sur d’autres sites (13055)
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Error with FFmpeg and FS in React : "ErrnoError : FS error"
23 juillet 2024, par namwanI'm working on a React application where I'm using the @ffmpeg/ffmpeg library to compress images and videos. I'm facing an issue with the virtual file system (FS) when trying to read and write files using FFmpeg. I'm getting the following error :


ErrnoError: FS error


Here's the relevant part of my code :


import React, { useState } from "react";
import { FFmpeg } from "@ffmpeg/ffmpeg";

const ffmpeg = new FFmpeg();

const fetchFile = async (filePath) => {
 const file = await ffmpeg.readFile(filePath);
 alert("hello");
 return new Uint8Array(file).buffer;
};


const Main = () => {
 const [file, setFile] = useState(null);
 const [compressedFile, setCompressedFile] = useState("");

 const loadFFmpeg = async () => {
 if (!ffmpeg.isLoaded) {
 await ffmpeg.load();
 }
 }; 

 const getFile = (event) => {
 const selectedFile = event.target.files[0];
 
 if (selectedFile) {
 setFile(selectedFile);
 }
 };

 const compressImage = (selectedFile) => {
 const img = new Image();
 img.src = URL.createObjectURL(selectedFile);
 img.onload = () => {
 const canvas = document.createElement('canvas');
 const MAX_WIDTH = 300;
 const MAX_HEIGHT = 300;
 let width = img.width;
 let height = img.height;

 if (width > height) {
 if (width > MAX_WIDTH) {
 height *= MAX_WIDTH / width;
 width = MAX_WIDTH;
 }
 } else {
 if (height > MAX_HEIGHT) {
 width *= MAX_HEIGHT / height;
 height = MAX_HEIGHT;
 }
 }

 canvas.width = width;
 canvas.height = height;
 const ctx = canvas.getContext('2d');
 ctx.drawImage(img, 0, 0, width, height);
 const dataUrl = canvas.toDataURL('image/jpeg', 1.0);
 setCompressedFile(dataUrl);
 };
 };

 const compressVideo = async (selectedFile) => {
 try {
 await loadFFmpeg();
 
 const arrayBuffer = await selectedFile.arrayBuffer();
 const fileName = selectedFile.name;
 
 await ffmpeg.writeFile(fileName, new Uint8Array(arrayBuffer));
 
 await ffmpeg.exec(
 '-i',
 fileName,
 '-vf',
 'scale=640:-1',
 '-c:a',
 'aac',
 '-strict',
 '-2',
 'output.mp4'
 );
 
 const data = await fetchFile('output.mp4');
 const compressedVideoBlob = new Blob([data], { type: 'video/mp4' });
 const compressedVideoUrl = URL.createObjectURL(compressedVideoBlob);
 setCompressedFile(compressedVideoUrl);
 
 await ffmpeg.unlink(fileName);
 await ffmpeg.unlink('output.mp4');
 
 alert('Compression successful');
 } catch (error) {
 console.error('Error:', error);
 alert('Compression failed. Please check the console for more details.');
 }
 };
 

 const handleSubmit = async (e) => {
 e.preventDefault();

 if (file) {
 const fileType = file.name.split('.').pop().toLowerCase();

 if (fileType === 'png' || fileType === 'jpg' || fileType === 'jpeg') {
 compressImage(file);
 } else if (fileType === 'mp4' || fileType === 'h264') {
 compressVideo(file);
 } else {
 alert('Please select a valid file type (png, jpg, jpeg for images or mp4, h264 for videos).');
 }
 }
 };

 const handleDownload = () => {
 if (file) {
 const downloadLink = document.createElement('a');
 downloadLink.href = compressedFile;

 const fileExtension = file.name.split('.').pop().toLowerCase();

 downloadLink.download = `compressed_file.${fileExtension}`;
 
 document.body.appendChild(downloadLink);
 downloadLink.click();
 document.body.removeChild(downloadLink);
 }
 };

 return (
 <>
 <h1>Main Page</h1>
 <form>
 <label>Upload</label>
 <input type="'file'" />
 <br /><br />
 <input type="submit" value="Compress" />
 </form>
 {compressedFile && (
 <>
 <h2>Compressed File Preview</h2>
 {file && file.name && ( 
 file.name.split('.').pop().toLowerCase() === 'mp4' || file.name.split('.').pop().toLowerCase() === 'h264' ? (
 <video width="300" controls="controls">
 <source src="{compressedFile}" type="video/mp4"></source>
 Your browser does not support the video tag.
 </video>
 ) : (
 <img src="http://stackoverflow.com/feeds/tag/{compressedFile}" alt="Compressed file preview" style='max-width: 300px; max-height: 300px' />
 )
 )}
 <br /><br />
 <button>Download Compressed File</button>
 >
 )}
 >
 );
};

export default Main;


I'm using ffmpeg.readFile and ffmpeg.writeFile to read and write files to FFmpeg's virtual file system. I've also tried using ffmpeg.read and ffmpeg.write but still encounter the same issue.


Could someone please help me understand what might be causing this FS error and how to resolve it ?


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How to averagely extract frames from a video using ffmpeg by specifying "fps"
14 juin 2021, par alanzzzI have a job of using ffmpeg to extract the frames averagely from a video, with different fps. I use this command for it.


ffmpeg -i input.mp4 -r specified_fps -q:v 2 image %4d.png

And I have 3 questions about this task.


- 

- what I expect is that if I double the fps, the number of extracted frames will also get doubled. However, that's not the case. Take one of the input videos as an example.




video info


- 

- Duration : 1min18s
- Total number of frames : 2340
- Frame rate mode : constant (CFR)
- Frame rate : 30.0 FPS










Config setting & results


- 

- FPS=1 => number of frames=80
- FPS=2 => number of frames=158 (2x80-2)
- FPS=3 => number of frames=236 (3x80-4)
- FPS=5 => number of frames=392 (5x80-8)










Is it possible for me to get the exact doubled number of frames when fps get doubled ? In such case, number of frames is 160 for FPS=2, 240 for FPS=3, 400 for FPS=5.


- 

-
I check for the output images, the extracted frames in different fps are totally different from each other. In other words, for example, the 1st image for fps=1 is not the same as the 1st image for fps=2. Is that legitimate ? And is it possible for me the get some identical images for different fps ?


-
The last problem is that for some videos I use, the difference between the 1st and 2nd image is different from the difference between the 2nd and 3rd. While for the remaining images, the differences become average. To be specific, there is only a slight change from 1st to 2nd frame, while for 2nd to 3rd, 3rd to 4th, and so on, the changes are the same, which is normally distributed according to the specified FPS. I am wondering why such a case happens ? Does it related to the I-frame, B-frame, P-frame, GOP or IDR ?








I am new to this field and cannot find some useful info from other places. I've tried my best to describe my questions clearly. Feel free to leave some comments. Any help would do me a great favor. Thanks in advance !


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ERROR : "Cannot Find FFMPEG" on Google Cloud Compute Engine Debian Wheezy 7.8 Managed Instance even though it's installed
17 mai 2021, par DynamoBoosterI wrote a Node.JS application that uses the
fluent-ffmpegmodule to watermark videos uploaded on the platform. I pushed the code to a my Google Cloud Compute Engine project, and every time I getError : Cannot Find FFMPEG. I ssh'd into the instance once it was created and ran these commands to installFFMPEGbefore actually testing out the code. I am not sure what is causing the error because after this I am positive thatFFMPEGis installed.


sudo apt-get update
sudo apt-get install -y ffmpeg
export FFMPEG_PATH="/usr/bin/ffmpeg"
export FFPROBE_PATH="/usr/bin/ffprobe"



Below is my FFMPEG code



function generate_thumbnail(name, path){
 logging.info("Generating Thumbnail");
 ffmpeg(path)
 .setFfmpegPath('/usr/bin/ffmpeg') 
 .setFfprobePath('/usr/bin/ffprobe')
 .on('end', function() {
 upload_thumbnail(name);
 logging.info("Thumbnail Generated and uploaded");
 return;
 })
 .on('error', function(err, stdout, stderr) {
 logging.info('ERROR: ' + err.message);
 logging.info('STDERR:' + stderr);
 })
 .on('start', function(commandLine) {
 logging.info(commandLine);
 })
 .screenshots({
 count: 1,
 filename: name + '_thumbnail.png',
 folder: 'public/images/thumbnails/'
 });
}


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