Recherche avancée

Sur d’autres sites (13439)

• How to get the thumbnail of base64 encoded video file in Nodejs ?

  3 octobre 2018, par Wai Yan Hein

  I am developing a web application using Nodejs. I am using Amazon S3 bucket to store files. What I am doing now is that when I upload a video file (mp4) to the S3 bucket, I will get the thumbnail photo of the video file from the lambda function. For fetching the thumbnail photo of the video file, I am using this package - https://www.npmjs.com/package/ffmpeg. I tested the package locally on my laptop and it is working.

  Here is my code tested on my laptop

  var ffmpeg = require('ffmpeg');
  
  
  
  module.exports.createVideoThumbnail = function(req, res)
  
  {
  
      try {
  
          var process = new ffmpeg('public/lalaland.mp4');
  
          process.then(function (video) {
  
  
  
              video.fnExtractFrameToJPG('public', {
  
                  frame_rate : 1,
  
                  number : 5,
  
                  file_name : 'my_frame_%t_%s'
  
              }, function (error, files) {
  
                  if (!error)
  
                      console.log('Frames: ' + files);
  
                  else
  
                      console.log(error)
  
              });
  
  
  
          }, function (err) {
  
              console.log('Error: ' + err);
  
          });
  
      } catch (e) {
  
          console.log(e.code);
  
          console.log(e.msg);
  
      }
  
      res.json({ status : true , message: "Video thumbnail created." });
  
  }

  The above code works well. It gave me the thumbnail photos of the video file (mp4). Now, I am trying to use that code in the AWS lambda function. The issue is the above code is using video file path as the parameter to fetch the thumbnails. In the lambda function, I can only fetch the base 64 encoded format of the file. I can get id (s3 path) of the file, but I cannot use it as the parameter (file path) to fetch the thumbnails as my s3 bucket does not allow public access.

  So, what I tried to do was that I tried to save the base 64 encoded video file locally in the lambda function project itself and then passed the file path as the parameter for fetching the thumbnails. But the issue was that AWS lamda function file system is read-only. So I cannot write any file to the file system. So what I am trying to do right now is to retrieve the thumbnails directly from the base 64 encoded video file. How can I do it ?

• Encoding audio_common messages to OPUS

  14 juin 2023, par djangbahevans

  ---

  


  I am trying to stream microphone and camera data to Amazon KVS WebRTC. I'm able to make video work using this package (adapted for noetic) however I am struggling to make audio work. I'm using the audio_capture package to get mp3 frames. I'm trying to convert this to OPUS frames before streaming to KVS, but I'm unsure how to do this. I wrote this bit of code based on the small resources I can find on using ffmpeg, but it's not working. avcodec_fill_audio_frame is returning -22.

  


  #include "opus_encoder.h"

OPUSEncoder::OPUSEncoder() {
  av_register_all();
  codecContext == nullptr;
}

OPUSEncoder::~OPUSEncoder() {
  if (codecContext != nullptr) {
    avcodec_free_context(&codecContext);
  }
}

int OPUSEncoder::Initialize(int Fs, int channels) {
  AVCodec *codec = avcodec_find_encoder(AV_CODEC_ID_OPUS);
  if (!codec) {
    printf("Codec not found\n");
    return -1;
  }

  codecContext = avcodec_alloc_context3(codec);
  if (!codecContext) {
    printf("Could not allocate audio codec context\n");
    return -1;
  }

  codecContext->sample_fmt = AV_SAMPLE_FMT_S16;
  codecContext->bit_rate = 128000;
  codecContext->sample_rate = Fs;
  codecContext->channel_layout = av_get_default_channel_layout(channels);
  codecContext->channels = channels;

  if (avcodec_open2(codecContext, codec, nullptr) < 0) {
    printf("Could not open codec\n");
    return -1;
  }

  return 0;
}

int OPUSEncoder::Encode(const uint8_t *audio_data, int frameSize,
                        uint8_t *out) {
  AVPacket pkt;
  av_init_packet(&pkt);
  pkt.data = nullptr;
  pkt.size = 0;

  AVFrame *frame = av_frame_alloc();
  frame->nb_samples = frameSize;
  frame->format = codecContext->sample_fmt;
  frame->channel_layout = codecContext->channel_layout;

  int ret = avcodec_fill_audio_frame(frame, codecContext->channels,
                                     codecContext->sample_fmt, audio_data,
                                     frameSize * 2, 0);
  if (ret < 0) {
    printf("Error filling audio frame: %d\n", ret);
    return -1;
  }

  ret = avcodec_send_frame(codecContext, frame);
  if (ret < 0) {
    printf("Error sending the frame to the encoder\n");
    return -1;
  }

  while (ret >= 0) {
    ret = avcodec_receive_packet(codecContext, &pkt);
    if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
      return 0;
    } else if (ret < 0) {
      printf("Error encoding audio frame\n");
      return -1;
    }

    memcpy(out, pkt.data, pkt.size);
    out += pkt.size;
    av_packet_unref(&pkt);
  }

  av_frame_free(&frame);

  return 0;
}


  


• ffmpeg file conversion AWS Lambda

  10 avril 2021, par eartoolbox

  I want a .webm file to be converted to a .wav file after it hits my S3 bucket. I followed this tutorial and tried to adapt it from my use case using the .webm -> .wav ffmpeg command described here.

  


  My AWS Lambda function generally works, in that when my .webm file hits the source bucket, it is converted to .wav and ends up in the destination bucket. However, the resulting file .wav is always 0 bytes (though the .webm not, including the appropriate audio). Did I adapt the code wrong ? I only changed the ffmpeg_cmd line from the first link.

  


  import json
import os
import subprocess
import shlex
import boto3

S3_DESTINATION_BUCKET = "hmtm-out"
SIGNED_URL_TIMEOUT = 60

def lambda_handler(event, context):

    s3_source_bucket = event['Records'][0]['s3']['bucket']['name']
    s3_source_key = event['Records'][0]['s3']['object']['key']

    s3_source_basename = os.path.splitext(os.path.basename(s3_source_key))[0]
    s3_destination_filename = s3_source_basename + ".wav"

    s3_client = boto3.client('s3')
    s3_source_signed_url = s3_client.generate_presigned_url('get_object',
        Params={'Bucket': s3_source_bucket, 'Key': s3_source_key},
        ExpiresIn=SIGNED_URL_TIMEOUT)
    
    ffmpeg_cmd = "/opt/bin/ffmpeg -i \"" + s3_source_signed_url + "\" -c:a pcm_f32le " + s3_destination_filename + " -"
    
    
    command1 = shlex.split(ffmpeg_cmd)
    p1 = subprocess.run(command1, stdout=subprocess.PIPE, stderr=subprocess.PIPE)

    resp = s3_client.put_object(Body=p1.stdout, Bucket=S3_DESTINATION_BUCKET, Key=s3_destination_filename)

    return {
        'statusCode': 200,
        'body': json.dumps('Processing complete successfully')
    }