IOS Mobile Feature Implementation

Project Description: Use first frame of processed video for saving memories and sending preview (Think about Snapchat).

Overview:

The original plan was to generate a thumbnail and use it. But it might be too much hassle to generate correct thumbnail. Available image generation facilities may lack support for this.

The alternative option is to pause the video session and stop rendering after first frame. This would still save computation resources and free them for transcoding.

There are 2 views taking care of the thumbnail:

1 SCPreviewConfigurationMediaView - it is used when user send snap from Opera (memories). Baked video is used, with color filter rendered on top. This is probably a low impact place because color filters are not that heavy. There might be thumbnail available here.

2 SCPreviewBlobMediaView - it is used when sending from Preview. Video is rendered with all filters live. UCO filters are heavy. So removing live rendering here would free a lot of resources for transcoding. There are options here:

1 Generate thumbnail as part of generateBlobWithUsingOriginalImage using getScreenshotAsynchronouslyWithRequest or something. It might not be that easy. there are a bunch of parameters but last time I checked it internally it was not always doing what we needed. Like when editing snap in memories and sending, I had troubles getting correct thumbnail.

2 Generate thumbnail in the view itself using SCVideoThumbnailGenerator. We would need to wire it in and setup. But it looks like it should work relatively straightforward.

3 Pause video after first frame is rendered. Video playback session has an option to skip rendering when paused using isOpera flag. So the setup would be to listen to first frame being rendered and then pausing video playback session. This would save less resources then thumbnail solution, but IMHO it is the easiest. We may go with it if other options are not feasible.

Summary:

Try to see if there is a thumbnail. There should be some sort of configuration comment to the view (preview configuration). If preview configuration has some sort of thumbnail, we could try to use it. If there is not a thumbnail, we will just run the video playback session as it is now, but we will pause it when it renders first frame. Goal is to save processing time. If there is a placeholder image, we can piggyback on it (Check “vide first frame image” or “video thumbnail image.”) You can see images in Xcode if you put a break point and then you can ender the image. So if any of those Images are present, we can leverage the code similar to above to create UI image view. Take a look at line 196, it is creating an image view. We can try the same. Create image view with the bounds and configure it the same way. If there is a placeholder image, thumbnail or video first frame try to use one of those. If those do n to work under the right conditions, then we can go into pausing the video. In video playback session, if the approach to thumbnails does not work, we can figure out how to pause video playback session. It starts playing and we pause immediately.

This project focuses on ONE file and should be done in Objective-C.

iPhone Mobile App Development Objective-C

Numer ID Projektu: #31378815

O projekcie