View Profile
View Forum Posts
Private Message
Hey, so as we know there are lots of YT downloading tools out there, many now supporting the new DASH format. Generally speaking I use ChrisPC VideoTube Downloader, it works nicely and always gets the best quality DASH video and 254kbps audio, if available. One issue with it though is that you have to pay for it to work with 1GB+ videos. So I looked for other programs, and got this - http://youtubedownloader.com/ which worked fine and got the 2.5GB video.
So just for curiosity sake I tried a smaller video with both programs, choosing 720p DASH on both (highest for this particular video) and wanted to see if they came out the same. They didn't. ChrisPC gave me this:
http://youtubedownloader.com/ gave me this:Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 3 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 28mn 10s
Bit rate : 2 035 Kbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 29.970 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.074
Stream size : 410 MiB (89%)
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 28mn 10s
Bit rate mode : Constant
Bit rate : 254 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 51.1 MiB (11%)
So quite different. Theoretically higher bitrate video on the latter, but theoretically better audio on the former. Why the disparity? I know DASH videos are not one complete file but surely there is only one "720p HD DASH" version on YT, isn't there? I've not had chance to analyse the video yet to see if the higher bitrate one truly does look better, but I demuxed the audio and looked at the spectrals of both, the ChrisPC audio does indeed have marginally better frequencies.Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=60
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 28mn 10s
Bit rate : 2 663 Kbps
Maximum bit rate : 4 656 Kbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 29.970 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.096
Stream size : 537 MiB (93%)
Tagged date : UTC 2014-02-14 21:16:37
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 28mn 10s
Bit rate mode : Variable
Bit rate : 192 Kbps
Maximum bit rate : 202 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 38.7 MiB (7%)
Title : IsoMedia File Produced by Google, 5-11-2011
Encoded date : UTC 2014-02-14 21:16:04
Tagged date : UTC 2014-02-14 21:16:37
Obviously my goal is to get the absolute best quality version saved on both video and audio, which if the above is anything to go by isn't as simple as you'd expect.
Support our site by donate $5 directly to us Thanks!!!
Try StreamFab Downloader and download streaming video from Netflix, Amazon!
Try StreamFab Downloader and download streaming video from Netflix, Amazon!
+ Reply to Thread
Results 1 to 7 of 7
-
-
Looks like it's mixing and matching audio & video. The youtubedownloader version has higher video bitrate, different encoding settings (High, 1 ref frame) but lower audio bitrate
Do you have a URL link to the YT video ? -
For "regular" DASH videos, youtube-dl is a good way to pick which version you want to mix & match
eg.
Here is a random DASH video https://www.youtube.com/watch?v=3JZ_D3ELwOQ
Code:youtube-dl -F https://www.youtube.com/watch?v=3JZ_D3ELwOQ
So I chose the 1080p version, with the highest quality audioCode:[youtube] Confirming age [youtube] 3JZ_D3ELwOQ: Downloading webpage [youtube] 3JZ_D3ELwOQ: Downloading video info webpage [youtube] 3JZ_D3ELwOQ: Extracting video information [youtube] 3JZ_D3ELwOQ: Downloading DASH manifest [info] Available formats for 3JZ_D3ELwOQ: format code extension resolution note 139 m4a audio only DASH audio 49k , audio@ 48k (22050Hz), 1.46M iB (worst) 171 webm audio only DASH audio 108k , audio@128k (44100Hz), 2.93M iB 140 m4a audio only DASH audio 129k , audio@128k (44100Hz), 3.89M iB 172 webm audio only DASH audio 180k , audio@256k (44100Hz), 4.55M iB 141 m4a audio only DASH audio 255k , audio@256k (44100Hz), 7.72M iB 160 mp4 256x144 DASH video 111k , video only, 3.31MiB 242 webm 426x240 DASH video 186k , video only, 4.65MiB 133 mp4 426x240 DASH video 256k , video only, 7.42MiB 243 webm 640x360 DASH video 373k , video only, 8.52MiB 134 mp4 640x360 DASH video 605k , video only, 11.11MiB 244 webm 854x480 DASH video 742k , video only, 16.19MiB 135 mp4 854x480 DASH video 1108k , video only, 20.86MiB 247 webm 1280x720 DASH video 1398k , video only, 29.80MiB 136 mp4 1280x720 DASH video 2214k , video only, 38.31MiB 248 webm 1920x1080 DASH video 2228k , video only, 51.11MiB 137 mp4 1920x1080 DASH video 4158k , video only, 73.91MiB 17 3gp 176x144 36 3gp 320x240 5 flv 400x240 43 webm 640x360 18 mp4 640x360 22 mp4 1280x720 (best)
Code:youtube-dl -f 137+141 https://www.youtube.com/watch?v=3JZ_D3ELwOQ -o "PATH\output.mp4"
Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 81.7 MiB
Duration : 4mn 13s
Overall bit rate : 2 700 Kbps
Writing application : Lavf56.12.100
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 3 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 4mn 13s
Bit rate : 2 440 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 23.974 fps
Maximum frame rate : 23.981 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.049
Stream size : 73.8 MiB (90%)
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 4mn 13s
Bit rate mode : Constant
Bit rate : 254 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 7.67 MiB (9%)
-
Thanks, I'll try out that tool shortly.
This was the video - https://www.youtube.com/watch?v=WkVcJ8r9vcM
So I just took a look myself with youtube-dl. It seems ChrisPC downloaded the highest DASH version but the other one downloaded the normal MP4 stream which is higher in size.
Is there a way to know which truly is the best video, or is the only way to dl the normal MP4 and see? I note that it says (best) next to the normal MP4 but I see that it did the same on yours, which obviously wasn't the case with the 1080p DASH there.139 m4a audio only DASH audio 50k , aac @ 48k (22050Hz), 9.59M
iB (worst)
140 m4a audio only DASH audio 129k , aac @128k (44100Hz), 25.61
MiB
171 webm audio only DASH audio 134k , audio@128k (44100Hz), 22.28
MiB
172 webm audio only DASH audio 216k , audio@256k (44100Hz), 32.62
MiB
141 m4a audio only DASH audio 257k , aac @256k (44100Hz), 51.41
MiB
278 webm 256x144 DASH video 172k , webm container, VP9, 15fps,
video only, 18.37MiB
160 mp4 256x144 DASH video 121k , 15fps, video only, 22.60MiB
242 webm 426x240 DASH video 248k , 30fps, video only, 36.67MiB
133 mp4 426x240 DASH video 254k , 30fps, video only, 49.36MiB
243 webm 640x360 DASH video 465k , 30fps, video only, 66.50MiB
134 mp4 640x360 DASH video 613k , 30fps, video only, 99.98MiB
244 webm 854x480 DASH video 939k , 30fps, video only, 135.15Mi
B
135 mp4 854x480 DASH video 1121k , 30fps, video only, 187.54Mi
B
247 webm 1280x720 DASH video 1928k , 30fps, video only, 268.41Mi
B
136 mp4 1280x720 DASH video 2232k , 30fps, video only, 410.90Mi
B
17 3gp 176x144
36 3gp 320x240
5 flv 400x240
43 webm 640x360
18 mp4 640x360
22 mp4 1280x720 (best)Last edited by Killer3737; 15th Jan 2015 at 18:17.
-
youtube-dl is supposed to download the "best" by default, automatically. That's what youtubedownloader gave you as well
However, there is a "better" audio in the dash version. So if assume that the higher bitrates are in fact "better" versions, you can mix & match the "best" video with the "best" audio
So it looks like chrispc downloader is downloading both dash versions, but there is a higher bitrate video MP4 version
Code:[info] Available formats for WkVcJ8r9vcM: format code extension resolution note 139 m4a audio only DASH audio 50k , audio@ 48k (22050Hz), 9.59M iB (worst) 140 m4a audio only DASH audio 129k , audio@128k (44100Hz), 25.61 MiB 171 webm audio only DASH audio 134k , audio@128k (44100Hz), 22.28 MiB 172 webm audio only DASH audio 216k , audio@256k (44100Hz), 32.62 MiB 141 m4a audio only DASH audio 257k , audio@256k (44100Hz), 51.41 MiB 278 webm 256x144 DASH video 172k , webm container, VP9, video only, 18.37MiB 160 mp4 256x144 DASH video 121k , video only, 22.60MiB 242 webm 426x240 DASH video 248k , video only, 36.67MiB 133 mp4 426x240 DASH video 254k , video only, 49.36MiB 243 webm 640x360 DASH video 465k , video only, 66.50MiB 134 mp4 640x360 DASH video 613k , video only, 99.98MiB 244 webm 854x480 DASH video 939k , video only, 135.15MiB 135 mp4 854x480 DASH video 1121k , video only, 187.54MiB 247 webm 1280x720 DASH video 1928k , video only, 268.41MiB 136 mp4 1280x720 DASH video 2232k , video only, 410.90MiB 17 3gp 176x144 36 3gp 320x240 5 flv 400x240 43 webm 640x360 18 mp4 640x360 22 mp4 1280x720 (best)
Code:youtube-dl -f 22+141 https://www.youtube.com/watch?v=WkVcJ8r9vcM -o "foo.mp4"
Code:Format : MPEG-4 Format profile : Base Media Codec ID : isom File size : 589 MiB Duration : 28mn 10s Overall bit rate : 2 923 Kbps Writing application : Lavf56.12.100 Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3.1 Format settings, CABAC : Yes Format settings, ReFrames : 1 frame Format settings, GOP : M=1, N=60 Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 28mn 10s Bit rate : 2 663 Kbps Width : 1 280 pixels Height : 720 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 29.970 fps Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.096 Stream size : 537 MiB (91%) Audio ID : 2 Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Codec ID : 40 Duration : 28mn 10s Bit rate mode : Constant Bit rate : 254 Kbps Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 44.1 KHz Compression mode : Lossy Stream size : 51.1 MiB (9%)
-
Originally Posted by Killer3737
I don't know... too bad the specs aren't listed for the "best" version in that list -
Ok thanks, yeah that'd be handy. I guess for now I'll just grab the normal version for 720p videos first and see if the size is larger than the DASH version listed.
PS would I be right in saying the 1080p DASH videos are lower quality than the old, pre-DASH 1080p videos? Because I have an old 1080p video downloaded in 2011 that is higher quality than the best 1080p DASH version available today.Last edited by Killer3737; 15th Jan 2015 at 19:14.
Quote