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• Video Conversion from cross platform (IOS, ANDROID, WEB) using FFMPEG [closed]

  1er août 2012, par Sunil Gulabani

  We are converting videos recorded from Apple IOS and Android device. And this converted videos are being accessed from IOS, android devices and Website using Strobe Media Playback.

  The videos are converted on Ubuntu Server.

  We are using following command to convert video :

  ffmpeg -i -s 480*800 -vcodec libx264 -acodec aac
  -strict experimental -ac 2 -r 25 -ab 44100 .mp4

  The issue come when uploading from the IOS device that orientation changes.

  By removing the "-s 480*800" the orientation issue solves, but android devices stopped playing the converted videos.

  Is there any way that the converted video plays well in IOS, Android devices and Web.

• How to create m3u8 playlist from mp4 video url ( stored in amazon S3 ) and store the video chunks ( .ts files) and .m3u8 file back to another S3 ?

  19 mai 2019, par dexter2019

  I am building an application where user can upload video and others can watch them later. I am aiming for HLS streaming of the video on the client side, for which the video format should be .m3u8. I am using node fluent-FFmpeg module to do the processing, however, I have a huge doubt, that, how to ensure that all the .ts files (chunks) are also stored back in s3 bucket along with the m3u8 file after ffmpeg processed the mp4 file ?

  Because the ffmpeg command only takes the location of the m3u8 file ? How handle it when I want the input and output location to be S3 ?

  Any help will be greatly appreciated.

  I am following the answer from this question Ffmpeg creating m3u8 from mp4, video file size , which is working absolutely fine in my local machine, how to achieve the same for s3 ?

• Correct way for working with raw data when encoding using FFmpeg

  25 avril 2020, par midnightcoffee

  I am working on the android library for encoding/decoding raw data through ffmpeg. Every example I found uses files, it either reads or writes to a file. However, I am using raw byte array representing RGBA  image for encoder input and byte array for encoder output. Lets focus on encoding part for this question.

  



  My function looks like this : 

  



  int encodeRGBA(uint8_t *image, int imageSize, int presentationTimestamp,
 uint8_t *result, int resultSize)


  



  Where image is byte array containing raw rgba image data, imageSize is length of that array, presentationTimestamp is just counter used by AVFrame for setting pts, result is preallocated byte array with some defined length (currently with size matching width x height) and resultSize is byte array length (width x height). Returned int value represents actually used length of preallocated array. I am aware that this is not the best approach for sending data back to java and this is also part of the question. Is there a better way for returning result ?

  



  Example found here for encoding, directly writes byte data to the frame->data[0] (different approach for different formats, RGBA or YUV). But google search for "ffmpeg read from memory" results in examples like this, this or this. All of them suggesting using AVIOContext.

  



  I am confused how to use AVFormatContext with AVCodecContext for encoding ?

  



  Currently I have encoder working using first approach and I am successfully returning results as described (with preallocated byte array). I would like to know if that is wrong approach ? Should I be using AVIOContext for handling byte arrays ?