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• ffmpeg image watermark on video first half of video on Bottom left and next half of video on Top Right

  23 novembre 2020, par qedsl

  I was playing with this for several hours, I couldn't make so thought of reaching for help, Can you please help me in framing the ffmpeg command to display the watermark Image on the video, For the Initial half video the watermark should be on the bottom left and for the rest half video the watermark shop be on the right top.

  


  Bottom left : ffmpeg -i input.mp4 -i logo.png -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy output.mp4

  


  Top right :
ffmpeg -i input.mp4 -i logo.png -filter_complex "overlay=main_w-overlay_w-5:5" -codec:a copy output.mp4

  


  Also, I had a look on this for Timeoverlay ffmpeg watermark first 30 second.

  


  How to merge all these and satisfy my requirements as mentioned above ?

  


• Efficient way to create variant playlists from mp4 for HLS

  3 mars 2021, par nnaj20

  I am totally new to video encoding and options, and just learned about Apple's HLS requirements.

  


  So far, I've been able to get something working for my iOS app. However, I find the entire process to be very slow and manual. Now, having to repeat this for several more locales (video translations), I can't imagine there isn't a better way.

  


  Controlling bitrate

  


  To have control over the bitrate, I use HandBrake to create a new .mp4 file with the appropriate video encoder setting, for each bitrate I want (192k, 400k, 1m, etc.). THEN, I move onto creating the playlists. This alone takes several minutes—is there a better way ? tsrecompressor seemed close, but it just streams to a local port and doesn't save any playlists.

  


  Creating playlists from MP4

  


  Then I use Apple's suite of command-line tools (mediafilesegmenter, variantplaylistcreator, mediastreamvalidator, hlsreport) to generate the playlists, combine into a master playlist, validate, etc. I suppose this part could be somewhat automated with a script. I've seen others use FFMPEG, but I think the latter 3 Apple tools would still need to be sequentially applied.

  


  Do you see anything that can be obviously optimized ?

  


• Encoding uncompressed avi using RAWVIDEO codec and RGB24

  21 décembre 2020, par Heimmot

  I coded an encoder using FFMPEG (c++). The requirements for this encoder are :

  


  

  1. The output format should be uncompressed avi,

  


  2. Preferably using RGB24/YUV444 pixel format since we do not want chroma subsampling.

  


  3. Most standard players should support the format (windows media player (WMP), VLC)

  


  


  Using the encoder I wrote, I can write a number of file types right now :

  


  

  1. Lossless H.264 encoded video using the YUV420p pixel format and AVI container. (Obviously not uncompressed and chroma subsampled, however both WMP and VLC play without any problem.)

  


  2. MPEG4 encoded video using the YUV420p pixel format and AVI container.(Obviously not uncompressed and chroma subsampled, however both WMP and VLC play without any problem.)

  


  3. AYUV encoded video using the YUVA444P pixel format. (uncompressed as far as I understand and not chroma subsampled. However, VLC does not play this.)

  


  4. FFV1 encoded video using the YUV444P pixel format. (lossless, and not chroma subsampled. However, WMP does not play this.)

  


  


  The above is derived from this very usefull post.

  


  So I am now looking into the RAWVIDEO encoder from FFMPEG. I can't get this to work and neither can I find an example in the FFMPEG documentation on how to use this encoder for writing video. Can somebody point me in the right direction or supply sample code for this ?
Also, if there is another direction I should follow to meet my requirements feel free to point me to it.

  


  Thanks in advance