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• How can I use ffmpeg to create a seamless looping gif ? [closed]

  27 juin 2024, par DavidNyan10

  I have an MP4 file which contains animation repeating in a loop. Let's just say, for example, a video of rain. However, when loop is turned on, the video cuts off at the wrong place and does not make a nice smooth animation. The part where it loops is obvious. It's just that the video contains more than one cycle of the loop, but not an exact integer of the full cycle.

  


  My goal is to turn this video into a gif with a seamless loop. In other words, I want the last frame of the video to match the first frame.

  


  My approach : I found a "Seamless loop creator" website on Google, tried it out, and it worked REALLY well. I thought all my problems have been solved. But little did I know, I've been only looking at the few seconds at the beginning and at the end of the video, not paying attention to what's in the middle. The sneaky pesky little website cuts off the video right in the middle, stitch the "seamless transition" at the beginning and end of the video, and put an ugly cross-fade in the middle where the frames don't line up. That is stupid. This of course, isn't noticable on rain videos, but on videos like a character jumping, the crossfade is very visible.

  


  My second approach : I'd use FFMPEG to get the first frame of the video, then starting from the last frame of the video and backwards, it'd try to find a frame that matches exactly with the first frame.

  


  Steps :

  


  

  1. Get the first frame and save it as a PNG or something I don't know

  


  2. Reverse the original video

  


  3. Match the image to each frame of the video in step 2. It is now easier because it's not doing it backwards frame by frame.

  


  4. When a frame match is found, cut off all the frames before this matched frame.

  


  5. Reverse back the video

  


  


  Can I achieve something like this in ffmpeg, preferably a one-liner in windows cmd ?

  


  Follow-up question : Would it be better to leave the last frame the same as first frame or should I remove it ? For example, when it's looping, it would repeat that exact frame two times, is that good ? Or which one provides better results ? And if it's better to not include the last frame (the one that matches), how would I do it in my process above ?

  


  I tried ChatGPT, expecting a ready-made code. Put it in the command prompt and lost my original video file. Had to use a recovery tool because the file was overwritten.

  


• How to upload 7MB GIF to Twitter's API

  22 février 2021, par randombits

  I have a bunch of JPEG frames that I use ImageMagick to stitch together into a GIF. The final product has the following type :

  


  GIF image data, version 89a, 1280 x 720

  


  This gives the effect of an animated GIF. My file sizes range anywhere between 6-8MB.

  


  If I upload this media manually to Twitter, it works great. Using TwitterOAuth PHP library found here when I attempt the following :

  


  $media = $twitterConnection->upload('media/upload', ['media' => 'my_file.gif');

  


  I get the following error :

  


  Image file size must be <= 5242880 bytes

  


  I have also tried uploading the file using Twitter's recommended Python large video library and that failed with the following :

  


  INIT
Media ID: 1362940800456351744
APPEND
4194304 of 7685061 bytes uploaded
APPEND
7685061 of 7685061 bytes uploaded
Upload chunks complete.
FINALIZE
{'media_id': 1362940800456351744, 'media_id_string': '1362940800456351744', 'media_key': '7_1362940800456351744', 'size': 7685061, 'expires_after_secs': 86400, 'processing_info': {'state': 'pending', 'check_after_secs': 1}}
Media processing status is pending
Checking after 1 seconds
STATUS
Media processing status is failed


  


  I am willing to use any platform/utility to get my video files uploaded to Twitter. What is my best bet to either :

  


  1 : Fix my file type to adhere to Twitter's requirements. Should it not be a GIF ? Should I be converting my still shot JPEG files to another format ?

  


  2 : Is there an API that Twitter has available that will allow the GIFs of these sizes to be uploaded ? Again, I can upload these files via the regular Twitter web UI client, but I cannot automate it via their API.

  


  How do I upload my GIF to Twitter using their API ?

  


• Remapping multiple Mp4 videos into a single one with ffmpeg

  21 septembre 2016, par Josep Bosch

  I’m interested in remapping multiple (6) MP4 videos into a high resolution final video according to lookup tables I calculated. The idea is convert 6 independent videos in a 360º video according to an equirectangular projection.

  
  Example of equirectangular video here

  Is there a way to do this remapping with ffmpeg or any other linux program ?
  Right now I’m extracting all the frames from the videos, creating the equirectangular individual images and joining them again into a video. There must be a better way for this...

  UPDATE :

  Following Mulyva’s suggestion I first remap each individual video using the remap filter. Those parts of the panoramic video not covered are interpreted like chromakey pixels using :

  ffmpeg -i videos/camera1.MP4 -i camera0_map_x_radius5.pgm -i camera0_map_y_radius5.pgm -lavfi remap -qscale 1 out0.MP4

  

  

  Then I try to overlay them using the chomakey filter :

   ffmpeg -i out0.MP4 -i out1.MP4 -filter_complex "[1:v]chromakey=0x12da11:0.2:0.2[chromakey_res];[0:v][chromakey_res]overlay=eof_action=pass[out]" -map "[out]" out.mp4

  As you can see, the final result has an undesirable green shadow. Any idea of how to remove it ?