H.264 VBR, 1 pass vs. 2

Is there any way to quantify the advantages of 1 pass vs. 2? I realize it depends, in part, on the source material, but I've run some tests on 15 second clips from a project that's 30 minutes long, and I don't see any noticeable difference in image quality. Also, the output file is only about 2% smaller with 2 passes than it is with 1. On the other hand, it takes me 30 minutes to render the 15 second clip (it's HD) with 2 passes, which would translate into 60 hours for the whole project, vs. 30 for 1 pass. Doesn't seem worth it to me, but I'm a newb. Is there something I'm missing?

> But more importantly, the question is, why is it taking 30 min. to render a 15 sec. clip?
I was wondering that, too, but having nothing to compare it to I just figured that's the way it was. How's your system configured? I'm running Windows 7 Ultimate x64 on a 2.33 GHz dual core Xeon with 16GB of RAM and dual WD VelociRaptor 600GB HDDs (10K RPM, 32MB cache) configured as a RAID 1 (for security, not speed) on a SATA I controller. My source is 1440 x 1080, 30 fps, AVCHD, and I'm outputting to 1920 x 1080, 30 fps, H.264. Both cores max out during the render.
It would be great if there were something relatively simple I could do to substantially reduce this time as I'm going to be doing more of this sort of thing and this experience has me looking at new PCs.

Similar Messages

H.264 vs H.264 Blu-ray VBR 2-pass bit rate presets ...

If I select H.264 1080i, 29.97fps VBR 2-pass PP CS6 is recommending a target bit rate of 30 mbps and a max of 40 mbps. However, if I switch to H.264 Blu-ray I get 25/30. I was curious if there are logical reasons here for the difference.
In case it matters ... home movie (birthday parties, spring break trip, etc.), target output is playback on PC and PS3, and then Blu-ray disc. I've given up on the one file concept and was leaning towards an .mp4 and then separate .m4v/.wav files to feed to Encore. Curious what you would set for bit rates, if you would go VBR 2-pass, etc. (encoding time is not an issue).
Thanks

Blu-ray has bitrate limitations that computer files don't. (That's my guess on why the difference.)
Anyway, a preset is nothing more than a starting point, not the final authority on what you can export.

Adobe Premier Elements 13 Missing VBR 2 Pass

I recently just got Adobe Premier Elements 13, I've used Elements 11 and 12 prior.
In the past versions I am able to select VBR 2-Pass rendering export for H.264 videos. Now, however, in this new version I only have the option of CBR or VBR, 1 Pass.
This is under AVCHD of course, selecting MP4, and customizing settings. I can input the bitrate I want, I can change the profile to High and 5.1, but no matter what I do there are only 2 radio buttons, either CBR or VBR, 1 Pass. There is no option for 2-pass VBR like there was in Premier Elements 12. I'd hate to have to downgrade to get VBR2 support.
Thanks

BrentJustice
Thanks for the reply.
I do not believe the following will be a quick answer route, but you could consider filing one of those Adobe Feature Request Bug Report Forms.
Adobe - Feature Request/Bug Report Form
For all intents and purposes, the Adobe Premiere Elements Forum is a user to user forum. However, when a new version of the program is released and at other
undefined times, an Adobe presence is noted in the form of posts from people identifying themselves as Adobe Staff or PRE_help. There have been several
of these appearances since September 24, 2014, release date of version 13 until now. Hopefully one of them will see this VBR, 2 Pass matter and offer some
insights on its apparent disappearance from many of the Advanced export settings. I am still wondering about the 2 options in the save dialog for the customized preset.
Neither seem usable. So, I leave the options unchecked. This latter matter applies to version 12 and 13.
Lots to explore and learn.
Best wishes
ATR

How much better is VBR 2 Pass than VBR 1 Pass or CBR?

Hi,
I had a 2 hour and 40 minute wedding on a Premiere Pro CS 5.5 Timeline. (I exported it as a QT Reference File from Final Cut Pro 7)
I added my Encore Chapter markers in PPro and went File ----- Export ---- Media.
Media Encoder opened and I set my settings the following way:
H.264 Blu-Ray
1440 x 1080 29.97 FPS
PCM Audio
Target Bit Rat = 18.5
Max Bit Rate 20
VBR 2 Pass
When it first started encoding it said that it was going to take 8 hours.
It has taken 14 Hours and it's finally finished.
My question is,
How much better is VBR 2 Pass than VBR 1 Pass or CBR?
The first pass of this job took about 3 and a half hours. The last 11 hours was the full 2 Pass.
Would VBR 1 Pass or CBR give a good enough quality as an H.264 Blu-Ray to give to clients.
Thanks in advance
Premiere Pro CS 5.5
Media Encoder 5.5
Encore 5
Mac Pro
10 GB RAM
2.66 GHZ Quad-Core Intel Xeon

Depends what you mean by "better". Multiple passes are done to reduce the file size (by more appropriate changes in bitrate for each moment in the footage). It's not designed to change the quality of the displayed frames, though it can have a small-but-noticeable quality effect on certain types of footage (e.g. a presentation that mixes static slides with high-motion video). If you can't see the difference in your footage, and you don't care about making the smallest possible file, VBR1 will get your clips done a lot faster.

Issues with Size of FLV VBR 2-pass vs 1-pass Encoding in CS6

Hey Everyone,
I've been doing some testing on various systems (using either Windows 7 or Windows 8 Consumer Preview) using Premiere Pro CS6 as well as Media Encoder 6 and I've noticed that encoding FLV files using VBR 2-pass encoding produces a file that is significantly larger than the same source file encoded using just a VBR 1-pass.
For example, one test that I ran used 10 seconds of DVCPRO HD 720P 29.97 footage as source material. I exported all clips exported as .flv, 960x540 square pixels, 29.97 fps, 1000 kbps and everything else left at default settings.
Here were my results:
Size of Export via Premiere Pro CS5 VBR 1pass: 1.564 MB
Size of Export via Premiere Pro CS5 VBR 2pass: 1.618 MB
Size of Export via Premiere Pro CS6 VBR 1pass: 1.450 MB
Size of Export via Premiere Pro CS6 VBR 2pass: 3.622 MB
Eric Addison of 100 Acre Films also ran a similar test on his system and got these results:
Encoding 10 secs of a P2 AVC-I 1280x720, 29.97 clip using the same settings as above to FLV
Premiere CS6 Export VBR 2 pass – 2.87 MB
Premiere CS6 Export VBR 1 pass – 1.55 MB
AME 6 Export VBR 2 Pass – 2.85 MB
I've tested this out with short clips, ~3 min sequences, raw clips, and clips with lots of effects, and I continue to get consistent results with the VBR 2-pass file being anywhere from 30% up to 300% larger than the same clip encoded using just 1-pass encoding. Again, this doesn't occur using Premiere Pro CS5 or 5.5 (or AME 5), so it appears to be just an issue within CS6.
Would anyone else be willing to run a similar test using their system and own source files and post your results in this thread to determine if this is a system-wide issue or just flukes?
Thanks!
Kevin Tostado
Tostie Productions

Just checking if there's any progress on this?
We're having a similar problem, I just made a bug report. -
Concise problem statement:
With CS6, rendering Flash Video files using AME creates files that are unuseable. They have bad flickering, and look like files that have been encoded with half the bitrate. This happens on all of our cs6 workstations, and has been happening since we moved to cs6. Our workaround is to render the file to a 30mbps H264 file, then open cs5.5 media encoder and transcode it to flash, where it renders them perfectly, as it used to! This is happening on projects where there have been no changes at all between cs5.5 and cs6 - we can render exactly the same timeline out of premiere pro in cs5.5 and it looks fine, then in cs6 it looks like crap.
Steps to reproduce bug:
Render an on2 vp6 flash video out of premiere pro.
Results:
Any parts of the video with gradients or hard colour contrast will look like crap, either blocky or blurry, like it's been encoded at a super low bitrate.
Expected results:
This is happening on all sorts of projects - stuff with titles generated in premiere pro, stuff with PNG files in it, stuff with sony EX1 footage, with segments of uncompressed video rendered in after effects,... basically everything.
Since filing the bug report, I've read this thread and worked out that like you guys it does only happen for us with 2 pass encoding. So at least now we have a better workaround than transcoding, we can just export in 1 pass. I don't like having to do that. Yes, probably loads of people can't tell the difference between 1 and 2 pass and blah blah blah other codecs are better, we all know that! We have to use on2 VP6, for lots of annoying reasons, one big one being that we have a lot of corporate clients who put our videos on their intranet, and don't let their staff update their media players, browsers, OS's etc. - so the only video they can reliably use for everyone is an on2 VP6 file. Anyway, would be great to have a fix, we're only just making back all the time we lost from having to transcode all our Sony EX1 footage that premiere pro cs6 couldn't deal with (that tearing issue is now fixed, thank f*ck). I doubt I'm going to be able to justify spending loads of money on upgrading to cs7 when it comes out after all the bugs we've had to deal with in this one.

Limiting h.264 VBR Peaks in FMLE

Hey, I'm currently streaming out content with large amounts of static image/little motion and then moments of rapid motion/moving image (1 minute of movement for every 5 of static shots, give or take)
Using h.264 VBR with this content gives peaks of bitrate way too high for our application, with a 450kbps stream peaking at 1.2mbps when the almost static content switches over to the fast moving video
Is there any method by which H.264 VBR can be limited in FMLE? What codec does FMLE use for h.264 encoding?
Thanks!

it would be great if Adobe had some one to answer these questions.. I would like to know if we can control VBR.. it spike to much

Adobe Premiere Elements 13 ne permet plus ceci : VBR 2 passes

Lors de l'export d'une vidéo, je ne peux pas exporter en "variable bit rate" VBR avec 2 passes. Cela était pourtant bien fonctionnel dans la version 12 d'Adobe Premiere.
Il semble que c'est un bug, mais qu'Adobe ne le corrige pas.
Voici d'autres forums qui parlent de ce problème :
- Adobe Premier Elements 13 Missing VBR 2 Pass
- Adobe Premier Elements 13 Missing VBR 2 Pass
- Premiere Elements 13: Bugs and shortcomings
- ATR Premiere Elements Troubleshooting: Premiere Elements 13 Daily Discoveries
J'ai contacté le support d'Adobe mais, ils n'ont pas de solutions... :-(

H.264 and multi-pass

This is weird. I am using the preset for H.264 10.3 mbps on 1080i HDV. It is just fine, but very slow. I wanted to make a comparison to a single pass encode. The only thing I changed is the "multi-pass" check box. But, the bitrate drops to about 1.6 mbps, and of course it looks like poo.
This makes no sense to me. What is going on?

as well as YouTube sites. Some of my files are up to an hour long, and above.
There are quite a few videos on YouTube that are up to 3 hours long. If you are having issues uploading long YouTube movies, have you contacted their tech support?
(10.6.3)
Use Software Update to update your os and anything else that needs to be updated.

How does the VBR 2-Pass Preview Work?

In Adobe Media Encoder, it obviously doesn't show you a run through your project twice, so does it like estimate where it would be approximately AS IF it were going through it twice at the same time?

Though it does not address your question, if you have a Project that is failing and wish to know exactly where, it might be better to use 1 pass, and just watch the progress dialog to find out an approximate Timecode, where the failure takes place. Don't know how it is in CS4, but unfortunately, in previous versions, Render, or Export would fail, and the dialog box would close. This meant that one had to watch the progress carefully and hope to grab the Timecode, before the box closed. The best way around that was to just set up a video camera to shoot the screen. Go get a cup of coffee and let PrPro fail. Run back the tape in the video camera, and note the point that it failed. Go to that spot in the Timeline and investigate carefully.
Now, if this is not what you needed to do in the end, ignore my post.
As Harm mentions, you might get more useful info, if you tell us in detail what your problem is, and what you hope to accomplish. Very often, there's "more than one way to skin this cat." [I have no idea what any of us would do with a "skin-less cat," but there was an old thread in the Lounge on a "hairless cat... "]
Good luck,
Hunt

Adobe Media Encoder does not honor VBR target rate

CS6
H.264 VBR 2-pass video. AC3 audio. Multiplexer on
Targetted 18 Mbps. Ended up close to 35 Mbps. Audio is corect.
The issue only appears when multiplexer is on.
When multiplexer is off, the file size and bit rate looks normal:
Bit rate mode
: Variable
Maximum bit rate
: 35.0 Mbps
When multiplexer is on, the file size matches 35 Mbps. Note the extra "bit rate" line
Bit rate mode
: Variable
Bit rate
: 34.1 Mbps
Maximum bit rate
: 35.0 Mbps
Same thing goes for MPEG2-DVD
MPEG2-DVD VBR 2-pass video. AC3 audio. Multiplexer on, variable bitrate
Targetted 3.7 Mbps. Ended up around 4.3 Mbps.
The issue again is only when multiplexer is on.
When multiplexer is off, the file size and bit rate looks normal:
Bit rate mode
: Variable
Bit rate
: 3 586 Kbps
Nominal bit rate
: 9 000 Kbps
When multiplexer is on, the file size matches 35 Mbps.
Bit rate mode
: Variable
Bit rate
: 4 343 Kbps
Nominal bit rate
: 9 000 Kbps
Is this a feature or bug? I vaguely rememer this was mentioned before but can't find the thread.
Thanks

Howard Hoffman wrote:
It was my old thread http://forums.adobe.com/message/3922923
Wondering if Adobe ever look at these forums to find bugs to fix.
Possibly. But they definitely look here:
https://www.adobe.com/cfusion/mmform/index.cfm?name=wishform

AME CS5.5 freezes while encoding

I upgraded my iMac to OS X 10.9 (Mavericks) a couple weeks ago. I tried encoding a 30 minute 1080p video to H.264, VBR 1 pass and it freezes midway through the encoding process. It did this a few times and I never had this issue before upgrading the Mac OS. Any reason why I am having this issue?
Thanks!

Try either disabling GPU acceleration in PPRO before exporting to AME or queuing up only one job at a time.
There's a lengthy thread here on the forums about similar issues with AME CS5.5. One big thing to keep in mind is that the hang on AME's side is just a symptom--a result of a problem upstream--and there have been a number of different issues that all resulted in AME hanging while encoding. We fixed several of these issues in CS6, but at least a few known cases remain. So it's worth downloading the trial version of PPRO CS6 to see if your case is fixed.
Also, there are subtle differences in the particulars of the hang, such as whether it hangs in about the same spot with a given sequence--if so, then there's probably something about assets or effects/transitions at that point that is triggering the issue. If AME hangs at different points in a given encode, then it might be a resource issue on your system, such as RAM getting maxed out.

AVCHD encoding for Youtube

I recently got a new camcorder, the sony HDR-CX300 (full specs in the link below). The video format it uses creates mt2s files. When I play the videos back with windows media player they are fluid and look great. I'm not sure that when I import the footage into premiere pro cs4, that I'm doing thing properly because the playback is not that smooth. The specs of the camera say full HD 1920x1080i MPEG4 AVC/H.264. When I import the video into premiere pro, it reads these settings from the file:
File Path: ...\20100326225522.m2ts
Type: MPEG Movie
File Size: 5.5 GB
Image Size: 1440 x 1080
Pixel Depth: 32
Frame Rate: 29.97
Source Audio Format: 48000 Hz - compressed - Stereo
Project Audio Format: 48000 Hz - 32 bit floating point - Stereo
Total Duration: 01;04;18;11
Average Data Rate: 1.5 MB / second
Pixel Aspect Ratio: 1.3333
My confusion is about the difference in aspect ratio why does premiere think my video is 1440 x 1080 and not 1920 x 1080? My guess is it has to do with the pixel aspect ratio. I'm also unsure about the appropriate frame rate to use, 29.97 or 30fps? Also, is there any difference between using field upper / field lower for interlaced video? I tried both but did not notice any difference.
I know the post is long but if you could answer any of these questions, it would be greatly appreciated.
HDR-CX300 http://www.sonystyle.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10551&storeId= 10151&langId=-1 &productId=8198552921666073223#specifications

Interesting observation I'd like to share. So I re-encoded the video again using the same settings I first tried:
     AVCHD 1080i(60)
     Height 1440
     Width 1080
     FPS 29.97
     Field Order Upper
     Profile Main
     Level 4.0
     Format H.264
     VBR 2 Pass
     Target Bitrate 15Mbps
     Max Bitrate 20Mbps
When I opened the video in quicktime it looked like garbage. Strange interlacing effects appeared and the aspect ratio was incorrect. Then I opened the same video in windows media player and suprisingly it played back perfectly with very crisp picture and smooth motion. So the moral of the story is, not all video players are created equal even on the same computer.
Hope this helps someone else.

H.264 .mov files problem with 2-pass vbr in DVD SP4

I have converted some VHS tapes by connecting the VCR to my camcorder (as a AC/DC bridge) and the camcorder to my macbook pro via firewire, and record using FCP into .mov files.
However, these files are huge (13 GB for an hour), and so I shrinked them down by exporting them (using QT pro) into .mov file via h.264 codec.
However, when I try to convert these already shrinked .mov files into mpeg2 files via compressor 2 (so that I can made a DVD in DVD SP), the files become corrupt when I use 2-pass vbr. (Frame freezes on play back in DVD SP and QT pro). It's OK with 1 pass vbr though.
If I convert those huge .mov files via mpeg4 in QT pro rather than h.264, there is not problem with 2-pass vbr.
So my delemma is: shall I store the files using mpeg4, or h.264?
I am under the impression that h.264 gives a better quality for the same file size than mpeg4, but 2-pass vbr will give a better quality than 1-pass vbr if I want to burn it on a DVD.
Thanks in advance.

In general recompressing from VHS to your computer to H.264 (or MPEG 4) then to m2v is going to hurt quality, so if you are able to get extra Hard Drives and store that way, or even a inexpensive camera with a firewire in/out you are probably better off (though with VHS it may be hard to tell regardless)
Also if you at least go straight the first time to m2v and check to make sure it looks okay to you, you may want to make sure to do that first
That being said, H.264 and One-Pass should in all likelihood (I have not tried recently, did it a while ago just to test things) will be better than MPEG-4 2-Pass, depends on the settings. Also if you try 1-Pass H.264 it seems to work with Compressor.

VBR or CBR for H.264 Blu-Ray?

When encoding a 2 and a half hour H.264 Blu-Ray project from Media Encoder, is it better to use VBR 1 Pass, VBR 2 Pass, or CBR? I want it to be a total of 15 Gigs when it's done encding in Media Encoder.
When working in DVD Studio Pro, I always use CBR without a problem. Those were not Blu-Ray discs though.
My Target Bit Rate is at around 12
My Max Bit Rate is 25 or 20.
Media Encoder 5
Premiere Pro cs 5.5

Jim Simon wrote:
Neither. CQ mode is best.
http://tangentsoft.net/video/mpeg/enc-modes.html
http://www.videohelp.com/tools/XviD4PSP
For more information on a description of Constant Qiuality (CQ) vs Constant or Variable Bitrate (CBR, VBR) have a look here on page 5..
http://www.x264pro.com/wp-content/uploads/x264_PRO_Help.pdf
The Adobe bundled h.264 doesn't have CQ though so it's best to go with VBR vs CBR because it will steal bits from less complex frames before and after when it's needed. It will also allow short term bursts of information (up to the Maximum threshold) so that when bits are needed it can use them. - eg a scene change.
Also, do 2-pass. The first pass it will learn about when it's going to easy and hard to make frames. With that information on the second pass it can steal from the future since it knows that the future frames might not need many bits.
Also, if you have a very simple frame it will reduce the bitrate and save you on the total size. If you use Constant Bitrate you don't have any of these efficiencies.
Constant Quality doesn't look at the problem from a bit perspective. It makes a variable bitrate based on the quality of each frame you want to hit.
'hope that helps.

Difference between CBR and 2 pass VBR...

I used to always set DVDSP 3 encoder to the same bitrate and max bitrate, usually both at 7.0 VBR 2 pass, if the max is the same as the regular bitrate, am i wasting my time doing a 2 pass?
im just wondering if i set , lets say 1hr 10min, to 1pass CBR at 7, i can save lots of time and still have high quality, or does VBR 2pass (reg and max setting 7.0) make a better quality dvd, and if so why?
the reason i ask is because dvdsp4 forces the max rate higher then the regular rate now, it never did that before

I used to always set DVDSP 3 encoder to the same bitrate and max bitrate, usually both at 7.0 VBR 2 pass, if the max is the same as the regular bitrate, am i wasting my time doing a 2 pass?
Yes. If you set both average and max bitrate to the same number, it can't vary the bitrate.
It's probably wasting time even when average and max are different but close to each other... again, it can't really vary bitrate much and thus probably makes more sense to go CBR.
You're best off using VBR when you've got to vary the bitrate a LOT. Like average of 4.0 and max of 8.0.

H.264 VBR, 1 pass vs. 2

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