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• Write EPIPE after upgrade Node.js

  30 juillet, par Rougher

  I am using this code for detecting audio replay gain. It was working well with Node.js 16, but after upgrading to Node.js 22, it started crashing a few times in an hour with this error:

  write EPIPE
      at WriteWrap.onWriteComplete [as oncomplete] (node:internal/stream_base_commons:87:19) {
    errno: -32,
    code: 'EPIPE',
    syscall: 'write'
  }
  

  My original code was

  static getReplayGainVolume(audioData: Buffer) {
          // Calculate the mean volume of the audio file at the given filePath
          var ffmpeg = spawn('ffmpeg', [
              '-i', '-',
              '-af', 'replaygain',
              '-f', 'null', '/dev/null',
              '-hide_banner', '-nostats'
          ]);
  
          var output = '';
  
          ffmpeg.stdin.write(audioData);
          ffmpeg.stdin.end();
  
          return new Promise((resolve,reject)=>{
              ffmpeg.on('error', function (err: any) {
                  reject(err);
              });
              
              ffmpeg.on('close', function (_code: any) {
                  // [Parsed_replaygain_0 @ 0000000002a2b5c0] track_gain = +6.53 dB
                  if (!output.includes("track_gain")) {
                      reject(output);
  
                      return;
                  }
  
                  const gainWithDb = output.split("track_gain = ")[1];
                  if (!gainWithDb) {
                      reject(output);
  
                      return;
                  }
  
                  const gain = gainWithDb.split(" dB")[0];
                  if (!gain) {
                      reject(output);
  
                      return;
                  }
  
                  resolve(parseFloat(gain));
              });
              
              ffmpeg.stderr.on('data', function (data: any) {
                  // ffmpeg sends all output to stderr. It is not a bug, it is a feature :)
                  var tData = data.toString('utf8');
                  output += tData;
              });
          });
      }
  

  Then after search in forums and Google, I improved (I hope I improved it with cleanups)

  static getReplayGainVolume(audioData: Buffer): Promise {
          return new Promise((resolve, reject) => {
              const FFMPEG_PATH = 'ffmpeg'; // Adjust this if ffmpeg is not in system PATH
              const FFMPEG_TIMEOUT_MS = 30 * 1000; // 30 seconds timeout for FFmpeg execution
  
              let ffmpeg: ChildProcessWithoutNullStreams;
              let output = ''; // Accumulate all stderr output
  
              // Timeout for the FFmpeg process itself
              const ffmpegTimeout = setTimeout(() => {
                  log.error(`[FFmpeg] FFmpeg process timed out after ${FFMPEG_TIMEOUT_MS / 1000} seconds. Killing process.`);
                  if (ffmpeg && !ffmpeg.killed) {
                      ffmpeg.kill('SIGKILL'); // Force kill
                      reject(new Error(`FFmpeg process timed out and was killed.`));
                  }
              }, FFMPEG_TIMEOUT_MS);
  
              // --- Define cleanup function to be called on process exit/error ---
              const cleanup = (shouldReject = false, error?: Error | string) => {
                  clearTimeout(ffmpegTimeout); // Ensure timeout is cleared
  
                  // Remove all listeners to prevent leaks
                  // This is CRITICAL for long-running bots that spawn many child processes
                  ffmpeg.stdin.removeAllListeners();
                  ffmpeg.stdout.removeAllListeners();
                  ffmpeg.stderr.removeAllListeners();
                  ffmpeg.removeAllListeners(); // Remove process listeners
  
                  if (ffmpeg && !ffmpeg.killed) { // Ensure ffmpeg process is killed if still alive
                      ffmpeg.kill(); // Graceful kill (SIGTERM), then wait for exit. If not, then SIGKILL.
                  }
  
                  if (shouldReject) {
                      reject(error instanceof Error ? error : new Error(String(error)));
                  }
              };
  
              try {
                  ffmpeg = spawn(FFMPEG_PATH, [
                      '-i', 'pipe:0', // Read input from stdin (pipe:0)
                      '-af', 'replaygain',
                      '-f', 'null', '/dev/null', // Write output to null device (discard audio output)
                      '-hide_banner', '-nostats' // Suppress ffmpeg's initial info and progress stats
                  ], { stdio: ['pipe', 'pipe', 'pipe'] }); // Explicitly pipe stdin, stdout, stderr
  
                  // --- CRITICAL: Event Handlers for ffmpeg process ---
  
                  // 1. Handle errors during spawning or execution (e.g., ffmpeg not found)
                  ffmpeg.on('error', (err: any) => {
                      log.error(`[FFmpeg] Failed to spawn or execute FFmpeg process:`, err);
                      cleanup(true, new Error(`FFmpeg process error: ${err.message}`));
                  });
  
                  // 2. Accumulate stderr output (where replaygain results and ffmpeg errors are printed)
                  ffmpeg.stderr.on('data', (data: Buffer) => {
                      output += data.toString('utf8');
                  });
  
                  // 3. Handle process exit (success or failure)
                  ffmpeg.on('close', (code: number) => { // 'close' indicates process has exited
                      log.debug(`[FFmpeg] FFmpeg process exited with code: ${code}.`);
                      if (code !== 0) { // Non-zero exit code means failure
                          log.error(`[FFmpeg] FFmpeg process exited with non-zero code ${code}. Output:\n${output}`);
                          cleanup(true, new Error(`FFmpeg process failed with exit code ${code}. Output: ${output}`));
                          return;
                      }
  
                      // If successful exit (code 0), parse the output
                      if (!output.includes("track_gain")) {
                          log.error(`[FFmpeg] 'track_gain' not found in FFmpeg output (exit code 0). Output:\n${output}`);
                          cleanup(true, new Error(`'track_gain' not found in FFmpeg output. Output: ${output}`));
                          return;
                      }
  
                      try {
                          // Regex to parse track_gain (e.g., "+6.53 dB" or "-12.00 dB")
                          const gainMatch = output.match(/track_gain\s*=\s*([+-]?\d+\.?\d*)\s*dB/);
                          if (gainMatch && gainMatch[1]) {
                              const gain = parseFloat(gainMatch[1]);
                              log.debug(`[FFmpeg] Replay gain volume: ${gain} dB.`);
                              cleanup(); // Clean up on success
                              resolve(gain);
                          } else {
                              log.error(`[FFmpeg] Failed to parse gain from FFmpeg output. Output:\n${output}`);
                              cleanup(true, new Error(`Failed to parse gain from FFmpeg output. Output: ${output}`));
                          }
                      } catch (parseError: any) {
                          log.error(`[FFmpeg] Error parsing FFmpeg replay gain output:`, parseError);
                          cleanup(true, new Error(`Error parsing FFmpeg output: ${parseError.message}. Output: ${output}`));
                      }
                  });
  
                  // 4. Write audio data to ffmpeg's stdin
                  // This is the only write operation that could throw EPIPE in this function.
                  try {
                      ffmpeg.stdin.write(audioData);
                      ffmpeg.stdin.end(); // Close stdin to signal end of input
                  } catch (stdinError: any) {
                      log.error(`[FFmpeg] Error writing audioData to FFmpeg stdin:`, stdinError);
                      // This error means ffmpeg's stdin pipe closed unexpectedly.
                      // This is the direct equivalent of an EPIPE (Broken Pipe) at the child process level.
                      cleanup(true, new Error(`Failed to pipe audio data to FFmpeg stdin: ${stdinError.message}`));
                  }
  
              } catch (spawnError: any) { // Catch errors from the spawn call itself (e.g., FFMPEG_PATH is invalid)
                  log.error(`[FFmpeg] Error spawning FFmpeg:`, spawnError);
                  cleanup(true, new Error(`Failed to spawn FFmpeg process: ${spawnError.message}`));
              }
          });
      }
  

  But unfortunately I still get the same error. Has anyone encountered this problem? How can I solve it?

  I use ffmpeg version 4.2.7-0ubuntu0.1

• How can I decode MegaRace (93/94) .HNM videos ? — FFmpeg fails and legacy tools are missing [closed]

  29 juillet, par L P

  Goal

  • I want to convert the original full‑motion videos shipped with MegaRace (DOS, 1993/94) from Cryo’s proprietary HNM format into a modern, playable container (e.g. lossless AVI/PNG sequence).
  • Capturing the screen while the game runs is not an option: the target is the pure background animation (no sprites, no overlays, no DOSBox scaling filters, no subtitles).

  What I already have

  • Extracted all *.HNM files out of MEGARACE.DAT with Game Extractor.
    (Directory listing: 100+ files from AZUR.HNM to VWBT5.HNM.)
  • Verified that they are indeed Cryo HNM: the wiki pages [1] and [2] say MegaRace uses an early variant (v1/v2) written by Pascal Urro (might also used in 92's Dune, 95's Lost Eden etc.).
  • Tried FFmpeg (from latest to earliest) with ffplay -f hnm -i EXPLO.HNM, but every file aborts with invalid resolution and invalid data found when processing input. Same for ffprobe and ffmpeg -i.
  • Searched for legacy tools:
    • hnmdec / hnm2avi — no longer included in modern ScummVM‑Tools; seems to have been present at some point.
    • extract_cryo — source vanished.
    • Game Media Formats DirectShow Filters, by Valery Anisimovsky could, in theory, load the vendor codecs (CM6_*.dll) and expose them to DirectShow, but I haven't found the necessary Cryo DLLs shipped with MegaRace.
  • Looked at the DOSBox “Video Codec” folder – it only contains ZMBV (zmbv.dll, zmbv.inf), which is unrelated (that’s the codec DOSBox uses for screen‑capture).

  Environment

  • macOS Sequoia 15.5 on Apple Silicon (but I can boot Windows 11 ARM or use x86_64 VMs if the solution requires them).
  • No need for audio; video stream alone is fine.

  Why this matters

  • Archiving early FMV assets is part of game preservation. MegaRace’s CG backgrounds are unique and currently inaccessible without running the whole DOS game.

  What I’m looking for

  • Specifications or source code for the HNM v1/v2 codec.
  • A working decoder (CLI or library) for any platform so I can batch‑convert all files.
  • Pointers on how to patch FFmpeg’s current libavcodec/hnm4video.c to support the older variant.
  • Alternatively, hints on extracting the player’s built‑in decoder from MEGARACE.EXE (or ScummVM’s internal implementation, if any) and wrapping it.
  • Any lead, paper, or old DOS utility is appreciated!

• How to compile latest FFmpeg Library for Android ?

  29 juillet, par Timo Schuck

  Struggling to put together a working and generally best practice build of current FFmpeg. There seems to be no up-to-date documents or tutorials. What does exist is full of outdated links or build-scripts that do not work.

• Input path errors while running FFMPEG and keeping subdirectory structure [closed]

  29 juillet, par piet koos

  My goal is to reduce the size of all .ogg files found under the parent directory "Formatted", while keeping the sub-directories and files structure the same.

  Example

  .../Formatted/"test1, test2, test3 and so on"/"files.ogg"
  

  to

  .../Contributors/"test1, test2, test3 and so on"/"reduced_files.ogg"
  

  However. While the script runs ffmpeg it seems that the some input file paths gives "Error opening input: No such file or directory". eg. It either cuts off the 'h' of home or adds a '.' to the end of the file extension.

  "ome/user1/Downloads/Encoding/Formatted/test1/"file""
  

  or

  Parse error, at least 3 arguments were expected, only 1 given in string "oding/Formatted/test1/"file"
  

  Resulting in

  .../Contributors/"test1, test2, test3 and so on"/ with only a single file or missing .ogg files.
  

  I'm new to coding, any help is appreciated . I've tried echoing the variables to make sure they are correct but early on in the process echo "3" "$dirName" shows the absolute path being inrorrect.

  #!/bin/bash
  
  sourceDir=$HOME/Downloads/Encoding/Formatted
  destDir=$HOME/Backup/LEARN/Contributors
  
  find ~/Downloads/Encoding/Formatted/ -type f -name "*.ogg" | while IFS= read -r d; do
  #    find -name "*.ogg" 
      echo "1" "$d"
  baseName=$(basename "$d")
      echo "2" "$baseName"
  dirName=$(dirname "$d")
      echo "3" "$dirName"
  dirName_0=$(basename "$dirName")
      echo "4" "$dirName_0"
      echo "5" "$destDir"
  outputDir="$destDir/$dirName_0"
      echo "6" "$outputDir"
  outputPath="$outputDir/$baseName"
     
  #    echo "1" "$d"
  #    echo "2" "$baseName"
      echo "3" "$dirName"
  #    echo "4" "$dirName_0"
  #    echo "5" "$destDirecho"
  #    echo "6" "$outputDir"
  #    echo "7" "$outputPath"
  #    echo "8" "$destDir/$dirName_0/$baseName"
  #    echo "9" "$sourceDir"
  
      mkdir -p "$outputDir"
  
      ffmpeg -i "$d" -b:a 24k -acodec libopus -map_metadata 0 -map_metadata 0:s:0 "$outputPath"
   
  done
  
  For the first file found, *echo* returns:
  
  1 /home/user/Downloads/Encoding/Formatted/test/file1.ogg
  2 file1.ogg
  3 /home/user/Downloads/Encoding/Formatted/test
  4 test
  5 /home/user/Backup/LEARN/Contributors
  6 /home/user/Backup/LEARN/Contributors/test
  7 /home/user/Backup/LEARN/Contributors/test/file1.ogg
  8 /home/user/Backup/LEARN/Contributors/test/file1.ogg
  9 /home/user/Downloads/Encoding/Formatted
  
  Which is correct, but then for the next file found:
  
  1 ome/user/Downloads/Encoding/Formatted/test/file2.ogg
  2 file2.ogg
  3 ome/user/Downloads/Encoding/Formatted/test
  4 test
  5 /home/user/Backup/LEARN/Contributors
  6 /home/user/Backup/LEARN/Contributors/test
  7 /home/user/Backup/LEARN/Contributors/test/file2.ogg
  8 /home/user/Backup/LEARN/Contributors/test/file2.ogg
  9 /home/user/Downloads/Encoding/Formatted
  
  line 1 and 3 both miss a h from home? It does this for files in multiple folders.
  

• how to combine several video random any one to create 1 new video ? using ffmpeg ? [closed]

  28 juillet, par Sky Moon

  how to combine several video random any one to create 1 new video? for example, I have 10 videos: 01.mp4; 02.mp4 ... 10.mp4 I want to combine random 5 of them to create 1 video example: (01.mp4+ 03.mp4+ 04.mp4+ 06.mp4 + 08.mp4) = 1 new video

  (02.mp4+ 04.mp4+ 05.mp4+ 06.mp4 + 09.mp4) = 1 new video

  Similar: random combination of 50 videos of 1000 videos to create 1 new video?