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#1 2020-07-05 14:26

Help, video grabber DL test please?

Are you able to download any of these Webm videos? :
https://www.youtube.com/watch?v=RfXcGqzSvaI Webm with Vorbis Ogg 448 kbit/s soundtrack
https://www.youtube.com/watch?v=207ziMjUFzY Webm with Iibopus Opus 512 kbit/s soundtrack

If so, then:
1. Please download them as Webm streams
2. Please download SPEK http://spek.cc/
2. In SPEK, please click: file/open/all files, to open Webm files
3. In SPEK, please save the displayed spectrum as a png picture
4. Please give me a link to the spectrum picture

I am eager to see those spectrum pictures, to see if YouTube allows uploaded Webm files to retain their Ogg or Opus soundtrack untouched? Or if YouTube processes down the soundtrack to something inferior?

+++++++++

Please don't waste your time on downloading any mp4 streams for me. On March 28th 2016 YouTube slashed the sound quality of new HD uploads from Mp4 AAC 192 kbit/s HiFi to 126 kbit/s LoFi. I uploaded the test videos yesterday well after year 2016, so I know in advance that the mp4 streams are pure garbage. (Hint: never upload mp4 files to YouTube yourself...)

But I think I am on the verge of finding a new loophole to HiFi uploads at YouTube? Webm and/or MKV uploads might possibly be allowed to retain their Ogg/Opus soundtrack untouched by YouTube's video processing?

But YouTube started to block most video grabbers in mid-2019, so I cannot even download my own privates videos anymore. And I need to download them, in order to check with SPEK if the loophole exists or not.

Trying to ensure the best possible sound quality at YouTube is like playing chess against a semi-pro. So please help me to checkmate YouTube by downloading those Webm pawns if you can?

2020-07-06 14:08

Update:
What YouTube did upon upload:
Opus 512 kbit/s mixed down to Opus 160 kbit/s
Ogg 448 kbit/s converted to Opus 160 kbit/s
Both converted to AAC 128 kbit/s
Both converted to AAC 48 kbit/s

So both July 2020 YouTube videos contain three audio soundtracks, all three mixed down to lower bit rate that the original:
Opus 160 kbit/s
AAC 128 kbit/s
AAC 48 kbit/s

+++++++++

Conclusion (for uploaders): It's a good idea to upload your YouTube videos as Webm video, with Iibopus Opus soundtrack with at least 160 kbit/s audio bitrate. If you do so, you won't lose more than necessary in bitrate, it seems. Uploading as Opus when you'll get Opus will give you at least some sense of control.

+++++++++

Conclusion 1 for downloaders: Always only download the Webm stream from YouTube, if the video was uploaded after January 2019.

Conclusion 2 for downloaders: Disregard everything here, download all streams and examine them with SPEK, if the video was uploaded before April 2016.

Conclusion 3 for downloaders: If a YouTube video was uploaded between March 2016 and February 2019, then download all streams and examine them with SPEK, because a very tiny minority used a forgotten backdoor to HiFi throughout year 2016-2017. The minority is smaller than 0.1% of the channels, so in most cases: The Webm stream is the better one, if uploaded after March 2016.

(The backdoor was slammed shut sometime between January 2018 and January 2019. Sorry for the unknown date, but I didn't upload anything between those months.)