Best Handbrake settings for Youtube + Vimeo, plus a fragment of my doc.

Best Handbrake settings for Youtube + Vimeo

I'm writing this to keep track of my compression experiments and uploads. I have something of bearable quality here but I'm looking to make it better. To an extent, my dodgy camerawork and budget software means that my input signal will never be excellent (GIGO I know), but there's a lot you can do in Handbrake. I've messed around with advanced settings last night and got rid of some blockiness. The compression language is intimidating but there's a pop-up advice blimp that helps a lot.

95 per cent of viewers will watch my free film on Youtube or Vimeo so I'm prepared to work hard to improve the quality.

Handbrake has some advanced "High Profile" settings. When you whack them on high, quicktime can't deal with them, but can Youtube? Is it worth it?

I have some pictures of waves in water that turn to crap on upload. Any specific settings for dealing with waves?

First test fragment of documentary:

http://www.vimeo.com/17908188

There's a lot to do. I have to fix:

- The TV at the start is too black.
- The "Release the New Technology" title that flashes twice.


I'd never touched editing software a year ago. What I'm hoping is people will overlook some quality issues in exchange for some ideas they've never seen before, but I still want to do my best.

****

Appendix. Here are the settings I'm dealing with:

x264 Options in HandBrake
What they are
How to use them
QuickTime compatibility
Options explained
Examples
High Profile in HandBrake
What's in a name?
Other resources
What they are

Inside of any video codec, there are all sorts of different features and settings that can be turned on and off and given different values. Using different options can change the picture quality, file size, or encoding time. While the default options x264 applies are rather good, power users can tweak them depending on usage. For example, you might want to use different options for a cartoon than for an epic action-adventure.

How to use them

In the MacGui, there is an Advanced tab on the main window where you can add x264 options with pretty graphic buttons. From the command line, you can add them with --x264opts or -x. They are set up the same way as x264 options in MEncoder. That means they follow this format:

option1=value1:option2=value2:option3=value3
That is to say, each option's value is assigned with an equals sign (=), and each option-value pair is separated by a colon (:). One simple example would be:

bframes=6:me=umh:subme=5
Don't worry about what "bframes" or "me" or "umh" mean, quite yet. A full description of the options is provided further down in this guide.

Options explained

Sorry, this section is still incomplete. Currently, the best resource for x264 options is the MeGUI Wiki. Also check out MEncoder's documentation of x264 options

Frames

Reference Frames (ref)
Sane values are 1-6. The more you add, the higher the quality — but the slower the encode. Be careful...too many and QuickTime struggle to play the video back.

Mixed References (mixed-refs)
With this on, different references can be used for different parts of each macroblock, increasing quality.

B-Frames (bframes)
Sane values are 1-6. B-Frames are smaller than other frames, so they let you pack in more quality at the same bitrate. Use more of them with animated material: 9-16.

Direct Prediction (direct)
Direct prediction tells x264 what method to use when guessing motion for certain parts of a B-frame. It can either look at other parts of the current frame (spatial) or compare against the following P-frameframe (temporal). You're best off setting this to automatic, so x264 decides which method is best on its own. Don't select none assuming it will be faster; instead it will take longer and look worse. If you're going to choose between spatial and temporal, spatial is usually better.

Weighted B-Frames (weightb)
Sometimes x264 will base a B-frame's motion compensation on frames both before and after. With weighted B-frames, the amount of influence each frame has is related to its distance from the frame being encoded, instead of both having equal influence.

Pyramidal B-Frames (b-pyramid)
B-frame pyramids are a High Profile feature. This means that if you enable it, YOUR VIDEO WILL NOT PLAY IN QUICKTIME. Pyramidal B-frames mean that B-frames don't just reference surrounding reference frames — instead, it also treats a previous B-frame as a reference, improving quality/lowering bitrate at the expense of complexity. Logically, to reference an earlier B-frame, you must tell x264 to use at least 2 B-frames.

Motion

Motion Estimation Method (me)
Controls the motion estimation method. At the most basic setting, dia, x264 will only consider a diamond-shaped region around each pixel. The default setting, hex, is similar to dia but uses a hexagon shape. Uneven multi-hexagon, umh, searches a number of different patterns across a wider area and thus is slower than hex and dia but further increases compression efficiency and quality. esa, an exhaustive search of a square around each pixel (whose size is controlled by the me-range parameter), is only intended for experimentation and testing of algorithms and should not be used, as umh will generally produce as good or better results in vastly less time.

Motion Estimation Range (me-range)
This range is the radius, in pixels, x264 should use for motion estimation searches. It only has an effect when you use Uneven Multi-Hexagonal or Exhaustive searching. 24, 32, and 64 are good values.

Subpixel Motion Estimation (subme)
This setting is finer-grained than the motion estimation settings above. Instead of dealing with whole pixels, it deals with 4 fractional pixels, or quarter pixels (qpel). Higher levels increase quality by further refining the motion prediction for these quarter pixels, but take longer to encode. The default, 6, turns on a feature called rate distortion optimization, including psychovisual enhancements. 7 enables that rate distortion for B-frames. 8 refines those decisions for I and P frames, and 9 adds on refinement for B-frames as well.

Analysis

Analysis (analyse)
Analysis controls how finely x264 divides up a frame to capture detail. Full macroblocks are 16x16 pixels, but x264 can go down all the way to 4x4 blocks if it judges it necessary. By default it only breaks up key frames that much. To give x264 the freedom to make the best decisions for all frames, use "all" analysis. If you want to create a high profile H.264 video (which is less compatible with the world at large than main profile), also check the "8x8 DCT blocks" box to add yet another block size for analysis.

8x8 DCT Blocks (8x8dct)
When Analysis is set to "all," checking this box lets x264 break key frames down into 8x8 blocks of pixels for analysis. This is a high profile feature of H.264, which makes it less compatible. It should slightly decrease bitrate or improve quality.

Other

Deblocking (filter)
x264 includes an in-loop deblocking filter. What this means is that blocky compression artifacts are smoothed away when you play back the video. It has two settings: strength and threshold, just like a simple filter in Photoshop. Strength controls the amount of deblocking applied to the whole frame. If you drop down below 0, you reduce the amount of blurring. Go too negative, and you'll get an effect somewhat like oversharpening an image. Go into positive values, and the image may become too soft. Threshold controls how sensitive the filter is to whether something in a block is detail that needs to be preserved: lower numbers blur details less. The default deblocking values are 0 and 0. This does not mean zero deblocking. It means x264 will apply the regular deblocking strength and thresholds the codec authors have selected as working the best in most cases. While many, many people stick with the default deblocking values of 0,0, other people disagree. Some prefer a slightly less blurred image for live action material, and use values like -2,-1 or -2,-2. Others will raise it to 1,1 or even 3,3 for animation. While the values for each setting extend from -6 to 6, the consensus is that going below -3 or above 3 is worthless.

For more info, see .mp4 guy's deblocking faq.

Trellis (trellis)
Trellis fine-tunes how bitrate is doled out, so it can reduce file size/bitrate or increase quality. A value of 2 forces it to be used more often than a value of 1, and should only be used for a 2nd pass.

No DCT Decimate (no-dct-decimate)
To save space, x264 will "zero out" blocks when it thinks they won't be perceptible by the viewer. This negligibly reduces quality, but in rare cases it can mess up and produce visible artifacts. This situation can be alleviated by telling x264 not to decimate DCT blocks. It increases quality but also bitrate/file size, so if you use it when you've specified a target bitrate you will end up with a worse picture than without it. However, when used with constant quality encoding, or if you boost the average bitrate to compensate, you might get a better result.

No Fast P-Skip (no-fast-pskip)
This can help with blocking on solid colors like blue skies, but it also slows down the encode.

CABAC Entropy (cabac)
CABAC, or context adaptive binary arithmetic coding, is used by x264 to reduce the bitrate needed for a given quality by 15%. This makes it very cool and very useful, and it should be left on whenever possible. However, it is incompatible with the iPod 5.5G, and makes the AppleTV struggle. So turn it off for those. CABAC is a kind of entropy coding, which means that it compresses data by making shorthand symbols to represent long streams of data. The "entropy" part means that the symbols it uses the most often are the smallest. When you disable CABAC, another entropy coding scheme gets enabled, called CAVLC (context adaptive variable-length coding). CAVLC is a lot less efficient, which is why it needs 15% more bitrate to achieve the same quality as CABAC.

Custom Quantization Matrix (cqm)
QuickTime incompatible -- A custom quantization matrix sounds intimidating, but all you really need to know is that it can improve picture quality. Some video gurus swear by them. Basically, the matrices allow variation in the amount of compression different types of visual information (noise, edges, textures...) receive. Using flat is the same as not applying a CQM. Using jvt is the "official" matrix, but you're better off downloading Sharktooth's matrix or one of MP4Guy's matrices. Just save them as text files, and enter the full path to the matrix as the option value.

Examples

For examples of different x264 option strings, look at the CLI equivalents of the presets.

High Profile

High Profile enables all the bells and whistles in the H.264 standard. It is then that the codec truly shines and proves it is superior to plain MPEG-4.

Here are Sharktooth's High Profile settings used by MEGui, a Windows video encoder. Note that it does not take advantage of every high profile feature, like a custom quantization matrix. Use it with 2-pass at a medium-to-high average bitrate (1500, plus or minus 500kbps):

ref=3:mixed-refs=1:bframes=3:b-pyramid=1:b-rdo=1:bime=1:weightb=1:subme=6:trellis=1:analyse=all:8x8dct=1:vbv-maxrate=25000
However, you might want something a bit more excessive, like this:

ref=6:mixed-refs=1:bframes=3:b-pyramid=1:weightb=1:subme=7:trellis=2:analyse=all:8x8dct=1:no-fast-pskip=1:no-dct-decimate=1:me=umh:merange=64:filter=-2,-1:direct=auto
Would that which we call an x264 option, by any other name seem as cryptic?

x264 is pretty flexible about what it will accept for option names.

First off, all underscores (_) are converted to hyphens (-).

Second, if a value isn't given for an option, the value is assumed to be 1.

Third, if an option name starts with "no" or "no-", that part gets chopped off and the value gets inverted. So "no-fast-pskip=1" is the same as "nofast-pskip=1" is the same as "no_fast_pskip" is the same as "fast-pskip=0".

Fourth, some options have synonyms:

deterministic == n-deterministic
level == level-idc
ref == frameref
min-keyint == keyint-min
filter == deblock
analyse == partitions
weightb == weight-b
direct == direct-pred
merange == me-range
mvrange == mv-range
mvrange-thread == mv-range-thread
subme == subq
qp == qp_constant
qpmin == qp-min
qpmax == qp-max
qpstep == qp-step
ipratio == ip-factor
pbratio == pb-factor
cplxblur == cplx-blur
Other resources

Robert Swain (superdump) has put together a nice list ranking how different options affect the time it takes to encode a video and its picture quality.
MEncoder's documentation of x264 options is beyond compare.
Doom9's H.264 forum is a wonderful resource--but be careful, they don't suffer n00bs lightly.
x264 Options Explained is a thorough, Windows-centric guide
 
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Here's the mp4 guy from Handbrake's FAQ on blockiness

In X264 there are two deblocking parameters, called Deblocking strength and Deblocking threshold. The strength parameter refers to Alpha Deblocking, while the Threshold Parameter refers to Beta Deblocking (Alpha and Beta Deblocking are the official names). When a deblock setting is written as X:X (for instance 0:0 or 2:-2) the first number is alpha deblocking, while the second is beta deblocking.

Alpha deblocking effects the overal amount of deblocking to be applied to the picture, higher values deblock more effectively, but also destroy more detail and cause the entire image to be softened. The default value of 0 is almost always sufficient to get rid of most blocking (especialy when using a cqm), but leaves the picture noticibly blurier. In general use this value should be no lower then -3 and no higher then 3. When using a cqm the authors recomended settings should be used as the default value, and shouldn't be altered by more then +/-2. Alpha Deblocking is the most important parameter in determining the overal sharpness of your encode.

Beta Deblocking is a bit more tricky to use, Beta Deblocking determines whether something in a block is a detail or not when deblocking is aplied to it. Lower values of Beta Deblocking apply less deblocking to more flat blocks with details present (but more deblocking to blocks without details), while Higher values cause more deblocking to be applied to less flat blocks with details present. Generally Beta Deblocking shouldn't be altered unless you are haveing problems with the default setting. Raising Beta deblocking is a good way to help get rid of ringing artifacts by aplying more aggressive filtering to blocks that aren't very flat. Lowering beta Deblocking is a good way to reduce the amount of DCT blocks without bluring the entire picture. A high value of beta deblocking will cause nonflat blocks to be deblocked more aggressively, while a low value will cause the opposite.

If you wan't to give your encodes a more detailed look and don't mind the occasional block try a setting of -2:-1. If you like a clean picture and don't mind a little bluriness try 1:2. A nice trick for anime is to use lower beta deblocking setting because it won't blur out lines as much that way.
 
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