Investigate Data compression

[ChrishonWyllie]

Compressing Data requires iOS 13.0, which may be too restricting.
Additionally, it seems that compressing Data results in a larger file so it seems unnecessary given the original file size

[johndpope]

when this video exports / https://d21m91m763fb64.cloudfront.net/videos/8acab1c0-7cb0-11eb-821a-9b4798e5df00-8secondz-video.mp4 the video gets incorrectly resized.

It would be nice to be able to bypass the compression to disk.

UPDATE - this fixed things for me for now.
playerView = URLVideoPlayerView(delegate: self, cacheLocation: .none)

[ChrishonWyllie]

Hi @johndpope
I'm having a bit of trouble reproducing this.
Would you mind sharing a screenshot of the video when it is incorrectly resized using the .fileSystem cacheLocation?

[johndpope]

was happening on the iphone12pro - maybe reproducible on simulator - it was like the video stretched to a 1/4 of the size. top - left quarter. I like this repo - and it was my approach to do prefetching here - TikTok seem to get 6 videos eagerly upon app start - I'm still unsure best way to do this.

[ChrishonWyllie]

Hmm, here's what I tried to reproduce it:

• iPhone 12 Pro Simulator
• cacheLocation: .none (as per your first comment)
  And here's a screenshot of the video. The first cell at the top is the link you provided: https://d21m91m763fb64.cloudfront.net/videos/8acab1c0-7cb0-11eb-821a-9b4798e5df00-8secondz-video.mp4

I'm not aware of the dimensions of the original video file, is this the incorrect dimension?

Also regarding TikTok and a few other social media apps, I'm still trying to see how they do that.
I agree, it seems as if there's some content that is already available and doesn't need to be fetched (or rather it doesn't appear to the user)

One approach could be to kick off the prefetching of the videos during the AppDelegate willFinish or didFinish phase.
I haven't tried that as of yet, however. Not sure if those few milliseconds before the view is displayed would give the impression that the videos were already downloaded.

[johndpope]

I think the results would be comparable to
Something as crude as
Uicollectionview / prefetch cells at index path
+1 - get video
+2 - get video
....
+6 - get video

[johndpope]

If you hit the URL you’ll see it’s a 9:16 format

uPDATE

this crude approach works

I want to use your code to simply pick up / merge from existing download. It seems you are the only one on GitHub who has achieved this. Will take another look at it when I have more bandwidth

https://gist.github.com/johndpope/8d4ecbdeb1ecb3188b55afc5282d544e

[ChrishonWyllie]

Ah yes, I see its in the 9:16 format. I'll spend some time to correct this.
Thank you for pointing this out.

[johndpope]

Hi Chrishon -
a tiny wishlist (if I may) - I'd like to be able to bypass the export / resizing - and just save original (bloated) video.
(BTW - I believe that export is running on background (as opposed to utility) thread - which may not run when battery is low. )

[ChrishonWyllie]

Hi John

Sure, I can do that. An option for bypassing the resizing will be provided.
And you are correct about the background vs. utility threads. I will address that as well.

[ChrishonWyllie]

Hi @johndpope

I have released a new version 0.8.94
The major changes are:

• Removed the default compression for videos. Instead the original downloaded video will be used. But there are options in the initializer for exporting to a lower quality.
• Replaced .background Qos with .utility
• Added resolution and aspectRatio properties to the URLVideoPlayerView to help with determining the proper frame requirements

As for the video you provided that had an aspect ratio of 9:16, I implemented some changes to the example to address this concern.
The cells will now resize based on the ratio of the video and the other elements within the cell.
I used your video to test this, but didn't include it in the final version since I wasn't sure if this was a public video.

Please take a look at the CHANGELOG for a little more detail, and let me know if you have any issues.

[johndpope]

great - I will test this out. thanks!

[johndpope]

fyi https://github.com/meganz/iOS/blob/532eae4ccf1db0396856084523de97a5070bb61e/iMEGA/AudioPlayer/AudioPlayer/AudioPlayer%2BEventObservers.swift

UPDATE
I was using KVO in my own code / but for whatever reason - it inexplicably crashing. found this nice code.
https://github.com/Zhcyn/PhotoCut/blob/7abab2dc4580f04b3aa2cd98b67a3ff0deca8e91/Player/Playback/PlayerObserver.swift

[ChrishonWyllie]

Hmm, there's have quite a few observers going on.
In the stopObserving() function, they clear the kvoObservers array, but I figured they would have to individually stop observing each one within the array, rather than setting to empty.

[johndpope]

Yes. I had to adjust my kvo approach to use this. I have some proprietary code base but I want to send you a snippet. I have introduced a state engine from gamekit to shift through the fetching / playable states. I also have prototyped using digger library but it is not as good as your approach as it kind of blocks user from viewing video until it has fully downloaded. Spent a few weeks on it but still not there. The good thing with digger is it provides some granular control over stopping and starting the workers / downloads. JP

…

On Saturday, May 1, 2021, Chrishon Wyllie ***@***.***> wrote: Hmm, there's have quite a few observers going on. In the stopObserving() function, they clear the kvoObservers array, but I figured they would have to individually stop observing each one within the array, rather than setting to empty. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#15 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACGZSTZTMUG3GYCFYECHELTLM52PANCNFSM4KFQMAAA> .

[ChrishonWyllie]

Yes. I had to adjust my kvo approach to use this. I have some proprietary code base but I want to send you a snippet. I have introduced a state engine from gamekit to shift through the fetching / playable states. I also have prototyped using digger library but it is not as good as your approach as it kind of blocks user from viewing video until it has fully downloaded. Spent a few weeks on it but still not there. The good thing with digger is it provides some granular control over stopping and starting the workers / downloads. JP
…
On Saturday, May 1, 2021, Chrishon Wyllie @.***> wrote: Hmm, there's have quite a few observers going on. In the stopObserving() function, they clear the kvoObservers array, but I figured they would have to individually stop observing each one within the array, rather than setting to empty. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#15 (comment)>, or unsubscribe https://github.com/notifications/unsubscribe-auth/AACGZSTZTMUG3GYCFYECHELTLM52PANCNFSM4KFQMAAA .

Sure, if you want me to take a look at it, you can email me privately if you prefer.

[ChrishonWyllie]

So for the granular control that you mentioned, Celestial provide the ability to pause and resume download tasks:

    func pauseDownload(for sourceURL: URL)
    // Usage: Celestial.shared.pauseDownloaf(for: someURL)
    
    func resumeDownload(for sourceURL: URL)
    // Usage: Celestial.shared.resumeDownloaf(for: someURL)

Those are essentially what the two prefetching APIs are doing under the hood, but this lets you pause/resume individual tasks.
These functions are independent of the URLVideoPlayerView or URLImageView
I need to update the docs to include these, if it wasn't mentioned.
However, there's a bug I noticed with this and working on it now (Update, resolved in version 0.8.118)

---

As for your code snippets, I'm not seeing any standout reasons why the video needs to wait for a complete download to begin playing.
I see the status observer for the .readyToPlay case, but I can't see whether the play() function is called when it hits that case.