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• passing additional values to s3 event notification for lambda consumption

  8 septembre 2017, par user1790300

  I have to write code in react-native that allows a user to upload videos to amazon s3 to be transcoded for consumption by various devices. For the processing after the upload occurs ; I am reviewing two approaches :

  1) I can use Lambda with ffmpeg to handle the transcoding immediately after the uploading occurs (my fear here would be the amount of time required to transcode the videos and the effect on pricing if it takes a considerable amount of time).

  2) I can have s3 pass an sns message to a rest api after the created event occurs and the rest api generate a rabbitmq message that will be processed by worker that will perform the transcoding using ffmpeg.

  Option 1) seems to be the preferable option based on a completion time perspective. How concerned should I be with using 1) considering how long video transcoding might take as opposed to option 2) ?

  Also, regardless, I need a way to pass additional parameters to lambda or along the sns messaging that would allow me to somehow associate the user who uploaded the video with their account. Is there a way to pass additional text-based values to s3 to pass along to lambda or along sns when the upload completes, as a caveat I plan to upload the video directly to s3 using the rest layer(found this answer here : http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html#RESTObjectPUT-responses-examples) ?

• ffmpeg : does drawbox safely erase content of video ?

  25 janvier 2023, par Crenguta

  I want to make a box completely unrecognizable in a video without any way of reconstructing its content. Is

  


  ffmpeg -y -i input_video -vf "drawbox=x=10:y=10:w=100:h=100:color=black@1.0:t=fill" ouput_video


  


  sufficient for that ?

  


  The command creates a black box at the desired location. I am just not sure if this cannot be undone.

  


• How to use the FFmpeg blackdetect filter for the following image

  17 septembre 2021, par dinesh47

  I am using FFmpeg to find the blackdetect from a mp4 video file. but for some reasons file with very low light or poor background at night get detected as black frame For sample i have attached the frame which detected as black

  


  My ffmpeg filter setting is "blackdetect=d=121:pix_th=0.00"

  


  my file has a resolution of 1280*720 and frame rate of 30 which uses decoder format of 4:2:0 YUV


  


  There are 2 Questions

  


  1.Why the ffmpeg lib detects this as black frame ?

  


  2.How to over come this ?