[YouTube] Show the actual filesize for the revised format 18

[NanaMizukiAnother7]

Checklist

• I'm requesting a site-specific feature
• I've verified that I'm running yt-dlp version 2022.06.22.1 (update instructions) or later (specify commit)
• I've checked that all provided URLs are playable in a browser with the same IP and same login details
• I've searched the bugtracker for similar issues including closed ones. DO NOT post duplicates
• I've read the guidelines for opening an issue
• I've read about sharing account credentials and I'm willing to share it if required

Region

Around the World

Example URLs

https://www.youtube.com/watch?v=y9MY6TdAqHQ

Description

Originally the format 18 has video average bitrate of 40k and a audio quality of 96k. However ,in its later days, it matched 134+140 formats to revise one format, but the later format has missing file size.

The downloader shows its actual file size as seen here:

[info] y9MY6TdAqHQ: Downloading 1 format(s): 18
[download] Destination: Don't Associate with Darren Pipster(Pip Pip).mp4
[download]  63.8% of 12.55MiB at    6.73MiB/s ETA 00:00

It should be the actual file size, not the average file size.

Average: 12.86MiB
Actual: 12.55MiB

Verbose log

[debug] Command-line config: ['-Uv', '-F', 'y9MY6TdAqHQ']
[debug] Encodings: locale cp1252, fs utf-8, pref cp1252, out utf-8 (No VT), error utf-8 (No VT), screen utf-8 (No VT)
[debug] yt-dlp version 2022.06.22.1 [a86e01e] (win32_exe)
[debug] Python version 3.8.10 (CPython 64bit) - Windows-7-6.1.7601-SP1
[debug] Checking exe version: ffmpeg -bsfs
[debug] Checking exe version: ffprobe -bsfs
[debug] exe versions: ffmpeg 2022-06-22-git-fed07efcde-full_build-www.gyan.dev (setts), ffprobe 2022-06-22-git-fed07efcde-full_build-www.gyan.dev
[debug] Optional libraries: Cryptodome-3.14.1, brotli-1.0.9, certifi-2022.06.15, mutagen-1.45.1, sqlite3-2.6.0, websockets-10.3
[debug] Proxy map: {}
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Latest version: 2022.06.22.1, Current version: 2022.06.22.1
yt-dlp is up to date (2022.06.22.1)
[debug] [youtube] Extracting URL: y9MY6TdAqHQ
[youtube] y9MY6TdAqHQ: Downloading webpage
[youtube] y9MY6TdAqHQ: Downloading android player API JSON
[debug] Loading youtube-nsig.9c24c545 from cache
[debug] [youtube] Decrypted nsig VKoVr1e5P7d8egUxIoo => hR97k93D6bQ3hA
[debug] Sort order given by extractor: quality, res, fps, hdr:12, source, codec:vp9.2, lang, proto
[debug] Formats sorted by: hasvid, ie_pref, quality, res, fps, hdr:12(7), source, vcodec:vp9.2(10), acodec, lang, proto, filesize, fs_approx, tbr, vbr, abr, asr, vext, aext, hasaud, id
[info] Available formats for y9MY6TdAqHQ:
ID  EXT   RESOLUTION FPS |  FILESIZE  TBR PROTO | VCODEC       VBR ACODEC      ABR     ASR MORE INFO
-------------------------------------------------------------------------------------------------------------
sb2 mhtml 48x27          |                mhtml | images                                   storyboard
sb1 mhtml 80x45          |                mhtml | images                                   storyboard
sb0 mhtml 160x90         |                mhtml | images                                   storyboard
139 m4a   audio only     |   3.69MiB  48k https | audio only       mp4a.40.5   48k 22050Hz low, m4a_dash
249 webm  audio only     |   3.52MiB  46k https | audio only       opus        46k 48000Hz low, webm_dash
250 webm  audio only     |   4.40MiB  58k https | audio only       opus        58k 48000Hz low, webm_dash
140 m4a   audio only     |   9.80MiB 129k https | audio only       mp4a.40.2  129k 44100Hz medium, m4a_dash
251 webm  audio only     |   8.37MiB 110k https | audio only       opus       110k 48000Hz medium, webm_dash
17  3gp   176x144      7 |   2.79MiB  36k https | mp4v.20.3    36k mp4a.40.2    0k 22050Hz 144p
160 mp4   256x144     30 |   1.11MiB  14k https | avc1.4d400c  14k video only              144p, mp4_dash
278 webm  256x144     30 |   1.12MiB  14k https | vp9          14k video only              144p, webm_dash
133 mp4   426x240     30 |   1.82MiB  24k https | avc1.4d4015  24k video only              240p, mp4_dash
242 webm  426x240     30 |   1.36MiB  17k https | vp9          17k video only              240p, webm_dash
134 mp4   640x360     30 |   2.83MiB  37k https | avc1.4d401e  37k video only              360p, mp4_dash
18  mp4   640x360     30 | ~12.86MiB 165k https | avc1.42001E 165k mp4a.40.2    0k 44100Hz 360p
243 webm  640x360     30 |   1.94MiB  25k https | vp9          25k video only              360p, webm_dash
135 mp4   854x480     30 |   4.29MiB  56k https | avc1.4d401f  56k video only              480p, mp4_dash
244 webm  854x480     30 |   2.71MiB  35k https | vp9          35k video only              480p, webm_dash
22  mp4   1280x720    30 | ~17.51MiB 225k https | avc1.64001F 225k mp4a.40.2    0k 44100Hz 720p
136 mp4   1280x720    30 |   7.38MiB  97k https | avc1.64001f  97k video only              720p, mp4_dash
247 webm  1280x720    30 |   4.49MiB  59k https | vp9          59k video only              720p, webm_dash
298 mp4   1280x720    60 |   9.80MiB 129k https | avc1.640020 129k video only              720p60, mp4_dash
302 webm  1280x720    60 |   6.70MiB  88k https | vp9          88k video only              720p60, webm_dash
299 mp4   1920x1080   60 |  16.64MiB 220k https | avc1.64002a 220k video only              1080p60, mp4_dash
303 webm  1920x1080   60 |   9.55MiB 126k https | vp9         126k video only              1080p60, webm_dash
308 webm  2560x1440   60 |  22.69MiB 299k https | vp9         299k video only              1440p60, webm_dash
315 webm  3840x2160   60 |  39.22MiB 518k https | vp9         518k video only              2160p60, webm_dash

[pukkandan]

The "actual" filesize can only be known after starting a connection to the URL. So the only way to implement this is to make an additional request per format which would significantly slow down the extraction. So this cannot be done by default. An option for activating this would however be possible.

But in that case, we can infer far more metadata by calling ffprobe on the URL #613 instead of directly making a request