I get a better quality with a 1-pass encoding...!
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I get a better quality with a 1-pass encoding...!
Everywhere i go it says that 2-pass encoding is way much better,
and i believe it, so can somebody explain that to me ?!
I made some test and the quality's better with 1-pass, especialy on the transitions dark/light, where it's full of squares with a 2-pass !
Settings are:
Format: AVI
Codec : MPG4/MP3
FPS: Same as source
Encoder: Xvid
Average Bitrate: 2000Kbps
Let me knowww...
Thanx
and i believe it, so can somebody explain that to me ?!
I made some test and the quality's better with 1-pass, especialy on the transitions dark/light, where it's full of squares with a 2-pass !
Settings are:
Format: AVI
Codec : MPG4/MP3
FPS: Same as source
Encoder: Xvid
Average Bitrate: 2000Kbps
Let me knowww...
Thanx
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- Joined: Mon Mar 26, 2007 12:07 am
Re: I get a better quality with a 1-pass encoding...!
I have had some similar experiences (with xvid +2pass). Seems random, though, so I never reported it.monsieurboo wrote:... full of squares with a 2-pass !
Settings are:
Format: AVI
Codec : MPG4/MP3
FPS: Same as source
Encoder: Xvid
Average Bitrate: 2000Kbps
Let me knowww...
Thanx
Didn't want to disappoint you Cavalicious.Cavalicious wrote:Look for comments by PuzZLeR
monsieurboo: Can I get you to paste the CLI query for your 1-pass and 2-pass settings? I have a suspicion you may be confusing CRF 1-pass with ABR 1-pass and I'm guessing that your final bitrates/file sizes may be different with each scheme.
With whatever codec you use today, you will never get better quality with 1-pass ABR over 2-pass ABR. Never. In my opinion, 1-pass ABR is an incomplete 2-pass ABR. It should be only used when a quick encoding is necessary and an exact file size, where quality is not important. It's just for a quick view on an iPod or something, not for archiving.
However 1-pass CRF is different (and no such thing as 2-pass CRF exists that I know of or is necessary).
If you're comparing 1-pass CRF with 2-pass ABR with x264 you will have a million arguments as to which is better at the same bitrate. Both are arguably very, very similar in quality.
With older ASP codecs like Xvid it's not true. 2-pass ABR wins easily in motion scenes, and CRF will win with some nicer looking still frames.
I say this from years of experience coming from the DivX end of things, which is a similar codec to Xvid.
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After reading this I tried the one pass and the only difference I see between the two options is the extra time it takes to do a two pass. Picture/Audio is exactly the same for me with a one pass vs. a two pass on the last two DVDs I have ripped.
The only things I change using HB is setting the bitrate to 2000 and setting constant quality to 76%
The only things I change using HB is setting the bitrate to 2000 and setting constant quality to 76%
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Um...which did you do:Bear Hunter wrote:After reading this I tried the one pass and the only difference I see between the two options is the extra time it takes to do a two pass. Picture/Audio is exactly the same for me with a one pass vs. a two pass on the last two DVDs I have ripped.
The only things I change using HB is setting the bitrate to 2000 and setting constant quality to 76%
set bitrate to 2000 (hence ABR)
-or-
Set to 76% (hence CQ)
its one or the other, not both.
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Yeah..ok, I figured that's why it greyed out. Bitrate at 2000Cavalicious wrote:Um...which did you do:Bear Hunter wrote:After reading this I tried the one pass and the only difference I see between the two options is the extra time it takes to do a two pass. Picture/Audio is exactly the same for me with a one pass vs. a two pass on the last two DVDs I have ripped.
The only things I change using HB is setting the bitrate to 2000 and setting constant quality to 76%
set bitrate to 2000 (hence ABR)
-or-
Set to 76% (hence CQ)
its one or the other, not both.
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I just did a search and a lot of reading. If the codec being used is .264 the CQ percentage is actually CRF? Or does CRF apply to the settings in the advanced tab? or both?Cavalicious wrote:I don't do CQ anymore, but I do CRF...and one would be hard-pressed not to be able to tell the difference between 2000 ABR and 76% CRF.
CRF is the way to go, try it and you'll see.
Advanced Prefs in the Mac GUI allow you to say CRF or CQ. There are CLI options for the same.Bear Hunter wrote:I just did a search and a lot of reading. If the codec being used is .264 the CQ percentage is actually CRF? Or does CRF apply to the settings in the advanced tab? or both?Cavalicious wrote:I don't do CQ anymore, but I do CRF...and one would be hard-pressed not to be able to tell the difference between 2000 ABR and 76% CRF.
CRF is the way to go, try it and you'll see.
Cheers, Ed.
CRF=76% is much too high when encoding from an MPEG-2 source. The law of diminishing returns begins to apply higher than 65% encoding from that older and limited format. Anything above 70% is really for raw uncompressed video which is 65GB/hour.
In fact, anything above CRF=70%, or even CRF=65% IMO, doesn't exist in MPEG-2. You will only be adding asymptotically low quality increments less than 0.01% but bloating file size tremendously, and unnecessarily.
Picture your video being a photograph, MPEG-2 being a cheap camera, H.264 being a high-powered camera/copy machine, and bitrate being ink.
It's like trying to make a photocopy of a picture better than the original by adding a ton more ink/toner - ain't gonna happen even with the best photocopier on the planet. You're better off taking the picture with a super camera. Instead you're only copying a picture from source to copier that was taken with a weak camera in between.
Save your ink.
In fact, anything above CRF=70%, or even CRF=65% IMO, doesn't exist in MPEG-2. You will only be adding asymptotically low quality increments less than 0.01% but bloating file size tremendously, and unnecessarily.
Picture your video being a photograph, MPEG-2 being a cheap camera, H.264 being a high-powered camera/copy machine, and bitrate being ink.
It's like trying to make a photocopy of a picture better than the original by adding a ton more ink/toner - ain't gonna happen even with the best photocopier on the planet. You're better off taking the picture with a super camera. Instead you're only copying a picture from source to copier that was taken with a weak camera in between.
Save your ink.
PuzZler: you always have great analogiesPuzZLeR wrote:Picture your video being a photograph, MPEG-2 being a cheap camera, H.264 being a high-powered camera/copy machine, and bitrate being ink.
It's like trying to make a photocopy of a picture better than the original by adding a ton more ink/toner - ain't gonna happen even with the best photocopier on the planet. You're better off taking the picture with a super camera. Instead you're only copying a picture from source to copier that was taken with a weak camera in between.
Save your ink.
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Sweet...thanks, I was looking in the "Advanced Tab" in the program itself. Looks like CRF was already checked. I'll run another DVD through it using CQeddyg wrote:Advanced Prefs in the Mac GUI allow you to say CRF or CQ. There are CLI options for the same.Bear Hunter wrote:I just did a search and a lot of reading. If the codec being used is .264 the CQ percentage is actually CRF? Or does CRF apply to the settings in the advanced tab? or both?Cavalicious wrote:I don't do CQ anymore, but I do CRF...and one would be hard-pressed not to be able to tell the difference between 2000 ABR and 76% CRF.
CRF is the way to go, try it and you'll see.
Cheers, Ed.
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So make sure CRF is checked in preferences and set the CQ to 65% max right?PuzZLeR wrote:CRF=76% is much too high when encoding from an MPEG-2 source. The law of diminishing returns begins to apply higher than 65% encoding from that older and limited format. Anything above 70% is really for raw uncompressed video which is 65GB/hour.
In fact, anything above CRF=70%, or even CRF=65% IMO, doesn't exist in MPEG-2. You will only be adding asymptotically low quality increments less than 0.01% but bloating file size tremendously, and unnecessarily.
Picture your video being a photograph, MPEG-2 being a cheap camera, H.264 being a high-powered camera/copy machine, and bitrate being ink.
It's like trying to make a photocopy of a picture better than the original by adding a ton more ink/toner - ain't gonna happen even with the best photocopier on the planet. You're better off taking the picture with a super camera. Instead you're only copying a picture from source to copier that was taken with a weak camera in between.
Save your ink.
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I can't comment on CQ since I have little experience with it and I'm on Windows so things are a bit different with the HB GUI there.Bear Hunter wrote:So make sure CRF is checked in preferences and set the CQ to 65% max right?
But, as Cavalicious said, CRF is the way to go as is my opinion too.
CQ is an older method, and CRF, although a bit slower, is an advanced and more adaptive version of CQ. CRF is subject to x264's perception of what quality is, and will adjust quantizer according to what x264 believes. The word is that x264 has good control over the flexiblity range of CRF, so more encoders are heading there.
So to answer your question with CRF instead of CQ, I'd say 65% is an upper limit if "small" file sizes are your still your goal. You can go 70% for a pinch more quality, but the file size will considerably escalate.
Anything over 70% is truly a waste of bitrate IMO. Files will start getting huge and quality gains will be microscopic...
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Thank you for your expertise... I'm a little confused though. I was under the impression that if CRF was checked in preferences...the CQ slider under the video tab would be how you adjusted it. Is there a different way to adjust CRF?PuzZLeR wrote:I can't comment on CQ since I have little experience with it and I'm on Windows so things are a bit different with the HB GUI there.Bear Hunter wrote:So make sure CRF is checked in preferences and set the CQ to 65% max right?
But, as Cavalicious said, CRF is the way to go as is my opinion too.
CQ is an older method, and CRF, although a bit slower, is an advanced and more adaptive version of CQ. CRF is subject to x264's perception of what quality is, and will adjust quantizer according to what x264 believes. The word is that x264 has good control over the flexiblity range of CRF, so more encoders are heading there.
So to answer your question with CRF instead of CQ, I'd say 65% is an upper limit if "small" file sizes are your still your goal. You can go 70% for a pinch more quality, but the file size will considerably escalate.
Anything over 70% is truly a waste of bitrate IMO. Files will start getting huge and quality gains will be microscopic...
Bear Hunter: you are correct. The constant quality slider *is*how you adjust a crf encode. By "CQ", puzzler is referring to "constant quantizer" which is one way x264 internally adjusts bitrate for quality, which is easy to confuse with the Constant Quality slider in the gui.Bear Hunter wrote: I'm a little confused though. I was under the impression that if CRF was checked in preferences...the CQ slider under the video tab would be how you adjusted it. Is there a different way to adjust CRF?
So, if you have crf checked in your preferences, HB will tell x264 to user crf, (constant rate factor method) and you adjust your percentages with the "Constant Quality" slider in the main window.
Basically just confusion between abbreviations.