@funkju remove the +++++, that just there to show what lines were added

@coschmit RCTVideo.m

Also confirming the patch is working with latest v5.1.0-alpha8

Add FFmpegMediaMetadataRetriever.OPTION_CLOSEST option to line 480 where bmp is generated to retrieve a frame that may or may not be a sync frame but is closest to or the same as time.

In reference to #255

@sidpauhal it seems the problem is not the URL but rather to find the exact frame for the given second.

If you have a look at the code of the Trimmer.java file on line 552 you will see this code for function getFrameAtTime()

FFmpegMediaMetadataRetriever.IN_PREFERRED_CONFIG = Bitmap.Config.ARGB_8888;
metadataRetriever.setDataSource(source);

bmp = metadataRetriever.getFrameAtTime((long) (sec * 1000000));
if(bmp == null){
  promise.reject("Failed to get preview at requested position.");
   return;
}

If there is no frame on that exact position the variable bmp will be null and hence, no image will be returned.

To overcome that a prop should be added to find the next available frame nearby.

bmp = metadataRetriever.getFrameAtTime((long) (sec * 1000000), FFmpegMediaMetadataRetriever.OPTION_CLOSEST);

I would open a PR @shahen94 but I have unfortunately no time right now.

I hope that helps.

Can confirm adding the FFmpegMediaMetadataRetriever.OPTION_CLOSEST option fixes thumbnail generation for certain videos that may not have an image at that exact time.