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• Read H264 streaming from Elp H264 with OpenCV + Python

  3 février 2017, par Francesco Paissan

  I’m trying to read an udp streaming of a H264 encoded image. The software structure is like follows :

  On a BeagleBoneBlack (Ubuntu 16.04) I’ve an Elp H264 cam (see here : https://www.amazon.com/ELP-Support-Android-Windows-Surveillance/dp/B00VDSBH9G ). I stream frames with ffmpeg on a Unicast UDP Stream.

  I want to read this images from python and opencv to be able to process them.

  I tried with this simple code to see if the cap is opened or not :

  import cv2

  try:
  
       cap = cv2.VideoCapture("udp://localhost:1234/")
  
      cap.set(CV_CAP_PROP_FOURCC, CV_FOURCC('H', '2', '6', '4'));
  
  except Exception, e:
  
      print str(e)

  But when I run this script python says :

  DtsGetHWFeatures : Create File Failed DtsGetHWFeatures : Create File
  Failed Running DIL (3.22.0) Version DtsDeviceOpen : Opening HW in mode
  0 DtsDeviceOpen : Create File Failed libva info : VA-API version 0.38.1
  libva info : va_getDriverName() returns -1 libva error :
  va_getDriverName() failed with unknown libva error,driver_name=(null)
  libva info : VA-API version 0.38.1 libva info : va_getDriverName()
  returns -1 libva error : va_getDriverName() failed with unknown libva
  error,driver_name=(null) libva info : VA-API version 0.38.1 libva info :
  va_getDriverName() returns -1 libva error : va_getDriverName() failed
  with unknown libva error,driver_name=(null) libva info : VA-API version
  0.38.1 libva info : va_getDriverName() returns -1 libva error : va_getDriverName() failed with unknown libva error,driver_name=(null)
  GStreamer Plugin : Embedded video playback halted ; module vaapidecode
  reported : Could not initialize supporting library. OpenCV
  Error : Unspecified error (GStreamer : unable to start pipeline ) in
  cvCaptureFromCAM_GStreamer, file /builddir/build/BUILD/opencv-
  2.4.12.3/modules/highgui/src/cap_gstreamer.cpp, line 816 /builddir/build/BUILD/opencv-2.4.12.3/modules/highgui/src/cap_gstreamer.cpp:816 :
  error : (-2) GStreamer : unable to start pipeline in function
  cvCaptureFromCAM_GStreamer

  Can anybody help me ?

  Thanks,

  Francesco.

• AWS Lambda function for modify video

  4 février 2017, par Gold Fish

  I want to create a Lambda function that invoked whenever someone uploads to the S3 bucket. The purpose of the function is to take the uploaded file and if its a video file (mp4) so make a new file which is a preview of the last one (using ffmpeg). The Lambda function is written in nodejs.
  I took the code here for reference, but I do something wrong for I get an error saying that no input specified for SetStartTime :

  //dependecies
  
  var async = require('async');
  
  var AWS = require('aws-sdk');
  
  var util = require('util');
  
  var ffmpeg = require('fluent-ffmpeg');
  
  
  
  // get reference to S3 client 
  
  var s3 = new AWS.S3();
  
  
  
  
  
  exports.handler = function(event, context, callback) {
  
      // Read options from the event.
  
      console.log("Reading options from event:\n", util.inspect(event, {depth: 5}));
  
      var srcBucket = event.Records[0].s3.bucket.name;
  
      // Object key may have spaces or unicode non-ASCII characters.
  
      var srcKey    =
  
      decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, " "));  
  
      var dstBucket = srcBucket;
  
      var dstKey    = "preview_" + srcKey;
  
  
  
      // Sanity check: validate that source and destination are different buckets.
  
      if (srcBucket == dstBucket) {
  
          callback("Source and destination buckets are the same.");
  
          return;
  
      }
  
  
  
      // Infer the video type.
  
      var typeMatch = srcKey.match(/\.([^.]*)$/);
  
      if (!typeMatch) {
  
          callback("Could not determine the video type.");
  
          return;
  
      }
  
      var videoType = typeMatch[1];
  
      if (videoType != "mp4") {
  
          callback('Unsupported video type: ${videoType}');
  
          return;
  
      }
  
  
  
      // Download the video from S3, transform, and upload to a different S3 bucket.
  
      async.waterfall([
  
          function download(next) {
  
              // Download the video from S3 into a buffer.
  
              s3.getObject({
  
                      Bucket: srcBucket,
  
                      Key: srcKey
  
                  },
  
                  next);
  
              },
  
          function transform(response, next) {
  
          console.log("response.Body:\n", response.Body);
  
          ffmpeg(response.Body)
  
              .setStartTime('00:00:03')
  
              .setDuration('10')   //.output('public/videos/test/test.mp4')
  
          .toBuffer(videoType, function(err, buffer) {
  
                          if (err) {
  
                              next(err);
  
                          } else {
  
                              next(null, response.ContentType, buffer);
  
                          }
  
                   });
  
          },
  
          function upload(contentType, data, next) {
  
              // Stream the transformed image to a different S3 bucket.
  
              s3.putObject({
  
                      Bucket: dstBucket,
  
                      Key: dstKey,
  
                      Body: data,
  
                      ContentType: contentType
  
                  },
  
                  next);
  
              }
  
          ], function (err) {
  
              if (err) {
  
                  console.error(
  
                      'Unable to modify ' + srcBucket + '/' + srcKey +
  
                      ' and upload to ' + dstBucket + '/' + dstKey +
  
                      ' due to an error: ' + err
  
                  );
  
              } else {
  
                  console.log(
  
                      'Successfully modify ' + srcBucket + '/' + srcKey +
  
                      ' and uploaded to ' + dstBucket + '/' + dstKey
  
                  );
  
              }
  
  
  
              callback(null, "message");
  
          }
  
      );
  
  };

  So what am I doing wrong ?

• Use Java FFmpeg wrapper, or simply use Java runtime to execute FFmpeg ?

  8 décembre 2024, par Beier

  I'm pretty new to Java, and need to write a program that listens to video conversion instructions and convert the video once a new instruction arrives (instructions are stored in Amazon SQS, but it's irrelevant to my question).

  


  I'm facing a choice, either use Java runtime to exec FFmpeg conversion (like from command line), or I can use an FFmpeg wrapper written in Java.

  


  http://fmj-sf.net/ffmpeg-java/getting_started.php

  


  I'd much prefer using Java runtime to exec FFmpeg directly, and avoid using java-ffmpeg wrapper as I have to learn the library.

  


  So my question is this : Are there any benefits using java-ffmpeg wrapper over exec FFmpeg directly using Runtime ?

  


  I don't need FFmpeg to play videos, just convert videos.