Constant Bit Rate Mode

[K Smith]

Even Apple with their crappy devices back in the early days of 1080p (think around 2010) was using High@L4

That’s not relevant. You may be thinking why I’m so into this why can’t I let go of this. But it’s really important that I should know if he is cheating. Obviously when you use a 15” monitor you won’t know the difference in quality. So that’s why I want to know i can prove mine is better than his rip. That’s all.

 

[Vzxy]

thanks for the reply. I completely agree with you. I’ve tried some “old” manual method to capture the stream and it was exactly the same as AS output. So that means AS is doing the same thing downloading the original stream and decrypting it.

I just want to know how to differentiate 2 videos with different bitrates

Really comes down to just watching it and judging for yourself. There's another thread on the forums here regarding exact same titles from AP, 4K vs 1080, and its basically the same thing. When Amazon gets a new 4K copy of an existing title they don't jsut delete the old one and only provide the 4K option. They will reencode 1080, 720, etc, from the new higher quality 4K source and have two different entries in the Prime video for that same movie. When they scale down from the 4K source it allows them to use different encoding options to create the 1080 fallback under that 4K title and it results in a different encoding with different bitrate and possibly a different profile since it doesn't need 5 reference frames to achieve the same visual quality as the other 1080 max version. And thats not to forget that encoders are getting better all the time. A version of ffmpeg from 2016 is not as efficient on the same settings as a version from today.

 

[0x0x0x0x0]

That’s not relevant. You may be thinking why I’m so into this why can’t I let go of this. But it’s really important that I should know if he is cheating. Obviously when you use a 15” monitor you won’t know the difference in quality. So that’s why I want to know i can prove mine is better than his rip. That’s all.

It's entirely relevant: providers code for devices, and there's literally no device that is capable of 1080p but can only cope with the Main Profile (that's what 720p devices "want"). Why would any provider waste storage bandwidth on something that is outside the spec??? He's not cheating, just using a screen recorder.

 

[cartman0208]

That’s not relevant. You may be thinking why I’m so into this why can’t I let go of this. But it’s really important that I should know if he is cheating. Obviously when you use a 15” monitor you won’t know the difference in quality. So that’s why I want to know i can prove mine is better than his rip. That’s all.

If both look the same and your filesize is smaller then yes, you win

 

[Vzxy]

it was a latest movie and 1080p. So I guess AS won’t be using main@ profile by any chance?

AS is just grabbing the source file at whatever profile it was encoded with. Sometimes that's a high profile and mostly its main. Try this: download a movie at 720 and 1080, you will most likely get a high profile encoding at 720 and 1080 will prolly be main profile. It really will depend on the movie, but this is what happens most of the time. Just different settings used to encode different resolutions.

 

[Vzxy]

Now that you've got me thinking about it I checked the last 30 files I've grabbed with AS and they're all high profile now. I guess AP may have changed some things. Or its very possible they have HLS transcoding in realtime from a high quality source. This is similar to what Kaltura Video server does in storing the one highest quality source file copy and then transcoding into an HLS stream on the fly based on client capabilities and preferences. I know most 1080 files I had gotten a month ago or so were all main profile encoding and now these last few I still have originals for are all high profile VBR CABAC 4 frames.

 

[zanetti]

I guess AP may have changed some things. Or its very possible they have HLS transcoding in realtime from a high quality source

hm, sounds interesting. if thats the case, wouldnt it be possible for amazon to switch transcoding quality between high and low when theres a high demand from users? that would explain a lot. e.g. 500000 concurrent users, amazon serves 14mbit CBR streams. 1500000 concurrent users, amazon serves 6mbit VBR streams. that would explain a lot. not everything, but a lot. if i had the time id pick a few titles and take two weeks of downloading them in 1080p at different points during the day. but i dont have that much time to spare, lol. but, i would if i had it, i need to know why i was served 14mbit 1080p stream for cliffhanger UHD and a measly 6mbit 1080p stream for non-UHD cliffhanger!!! theyre the same movie and resolution, damnit!!!! [cough] on the other hand, curiosity killed mr. mittens...

 

[K Smith]

Thanks for all the replies guys. Can someone confirm this pls. Let’s say there is a movie called ABC. It’s available in the Amazon.com.us and also in primevideo.com in Australia’s region. Do you think it’s possible for them to have a 8mbps stream in Australia and at the same time 10mbps stream in a he US for the same movie title?

 

[0x0x0x0x0]

yes

 

[Zoltan Sallay]

Not even amazon.com /.co.uk /.de etc has different versions you can find multiple version on primevideo.com as well. You can download few title from different release companies for example Shrek has a Universal and a DreamWorks version too on primevideo.com. All different bitrates sometimes in CBR newest ones VBR.

 

[towboat]

You can get CBR on any title, old or new, simply by overriding the getplaybackresouces request correctly. CBR is intended for old devices on Amazon, something of a legacy support. Usually VBR would be the way to go but not on Amazon. I don't know what encoding settings they use on it but it looks terribly blocky in 9/10 titles I've seen, especially in darker scenes. So your friend's rip is definitely better. He knows his stuff if the audio you got is the same. CBR playback means audio is restricted to AAC, so to get the good DD+ audio you also have to request VBR, get audio and switch to CBR for video. Download and combine both, resulting in the best possible version. A hybrid if you will. I've seen a few cases where VBR was better on Amazon, but they're a minority.

 

[0x0x0x0x0]

<snip>

Usually VBR would be the way to go but not on Amazon. I don't know what encoding settings they use on it but it looks terribly blocky in 9/10 titles I've seen, especially in darker scenes.

<snip>

Evidence?

 

[Anonyneko]

For anime AP most certainly has CBR files that are visually of a higher quality than VBR (I had an opportunity to compare), however AS will only download VBR. Shame (3D shows in particular look rather mediocre in VBR), but I can understand why developers won't enable CBR...

 

[Positions]

You can get CBR on any title, old or new, simply by overriding the getplaybackresouces request correctly. CBR is intended for old devices on Amazon, something of a legacy support. Usually VBR would be the way to go but not on Amazon. I don't know what encoding settings they use on it but it looks terribly blocky in 9/10 titles I've seen, especially in darker scenes. So your friend's rip is definitely better. He knows his stuff if the audio you got is the same. CBR playback means audio is restricted to AAC, so to get the good DD+ audio you also have to request VBR, get audio and switch to CBR for video. Download and combine both, resulting in the best possible version. A hybrid if you will. I've seen a few cases where VBR was better on Amazon, but they're a minority.

Easy to get CBR from AnyStream. fiddlerscript can be used to override getplaybackresouces.

 

[shower08]

Easy to get CBR from AnyStream. fiddlerscript can be used to override getplaybackresouces.

how to do this ? and which file

 

[EvilMonkey]

How many times must we discuss that Amazon's VBR is inferior to the CBR. The other method he is referring to definitely is not screen recorder because it is a pack of Chrome extensions but it is a much longer process than using something like AS because you're having to get all of the encryption keys and then finding the best stream for video and audio. Only a total noob would use screen recording software.

 

[EvilMonkey]

AS might not offer the best quality available but it's definitely not the worst. If I had a choice between only a HDTV recording or the prime video VBR with AS, then obviously AS would be the superior release.

 

[EvilMonkey]

Thanks for all the replies guys. Can someone confirm this pls. Let’s say there is a movie called ABC. It’s available in the Amazon.com.us and also in primevideo.com in Australia’s region. Do you think it’s possible for them to have a 8mbps stream in Australia and at the same time 10mbps stream in a he US for the same movie title?

Absolutely! It is very common for some regions to get a better release than others.

 

[shower08]

hello for my part I had a tool in python which had all the audio including video quality up to 2160p and in CBR which showed that it was better but the only problem is that it works no longer because of the change of CDM he would give me a new CDM with the L1 as before so that it works again, after anystream I have the + version but VBR too low in quality and at the moment not working on the software, after so that Anystream is functional at 100 % it would take an L1 CDM because amzn is blocked in L1 for 720p and 1080p and enable CBR.

 

[EvilMonkey]

hello for my part I had a tool in python which had all the audio including video quality up to 2160p and in CBR which showed that it was better but the only problem is that it works no longer because of the change of CDM he would give me a new CDM with the L1 as before so that it works again, after anystream I have the + version but VBR too low in quality and at the moment not working on the software, after so that Anystream is functional at 100 % it would take an L1 CDM because amzn is blocked in L1 for 720p and 1080p and enable CBR.

I see Amazon CBR releases all the time. That is about as far as I can discuss on that topic.