Recommend Encoding Setting x264 for Movie

[kiameliala]

Hi guys, im newbie as encoder. Anyone can help me to explain setting for x264?

Thanks before

[hello_hello]

It's generally not necessary to mess around with individual settings too much. The rule of thumb is to use the slowest speed preset you can stand, which adjusts individual settings for you, along with the desired CRF value to specify the quality. The idea is that a given CRF value should give you roughly the same quality relative to the source each time (assuming all other settings are the same), but as CRF encoding aims to produce a certain quality, the encoder will use whatever bitrate is required to give you that quality, so the bitrate and file size can vary quite a bit from one encode to the next depending on how hard the video is to compress. Noisy or grainy video will require a higher bitrate than "clean" video. The alternative is to use 2 pass encoding to specify the bitrate/file size you want, but then you have no control over the quality. It also takes longer as CRF encoding only requires a single pass. x264 also has several tuning options to adjust some of the individual settings automatically for you. I use the film tuning for most encodes.

For the CRF value, the lower the value the higher the quality and the higher the bitrate. The default is 23, but most people probably use a lower value. The CRF value can also be adjusted a little according to the resolution of the video. As lower resolutions are generally upscaled on playback, it means any encoder artifacts are also upscaled, so if anything you might want to use a slightly lower CRF value for lower resolution video. I generally use CRF 18 for standard definition, CRF 19 for 720p, and CRF 20 for 1080p.

Something like this in the x264 command line would be adequate. A level of 4.1 ensures the encoder will adjust a few settings if necessary (according to the frame rate and resolution) to ensure the encoded video can be played by most hardware players. Level 4.1 is supported pretty universally these days.

--level 4.1 --preset slower --tune film --crf 18.0

If you want to start messing around with individual settings, there's a description of them here:
https://en.wikibooks.org/wiki/MeGUI/x264_Settings

[kiameliala]

Originally Posted by hello_hello

It's generally not necessary to mess around with individual settings too much. The rule of thumb is to use the slowest speed preset you can stand, which adjusts individual settings for you, along with the desired CRF value to specify the quality. The idea is that a given CRF value should give you roughly the same quality relative to the source each time (assuming all other settings are the same), but as CRF encoding aims to produce a certain quality, the encoder will use whatever bitrate is required to give you that quality, so the bitrate and file size can vary quite a bit from one encode to the next depending on how hard the video is to compress. Noisy or grainy video will require a higher bitrate than "clean" video. The alternative is to use 2 pass encoding to specify the bitrate/file size you want, but then you have no control over the quality. It also takes longer as CRF encoding only requires a single pass. x264 also has several tuning options to adjust some of the individual settings automatically for you. I use the film tuning for most encodes.

For the CRF value, the lower the value the higher the quality and the higher the bitrate. The default is 23, but most people probably use a lower value. The CRF value can also be adjusted a little according to the resolution of the video. As lower resolutions are generally upscaled on playback, it means any encoder artifacts are also upscaled, so if anything you might want to use a slightly lower CRF value for lower resolution video. I generally use CRF 18 for standard definition, CRF 19 for 720p, and CRF 20 for 1080p.

Something like this in the x264 command line would be adequate. A level of 4.1 ensures the encoder will adjust a few settings if necessary (according to the frame rate and resolution) to ensure the encoded video can be played by most hardware players. Level 4.1 is supported pretty universally these days.

--level 4.1 --preset slower --tune film --crf 18.0

If you want to start messing around with individual settings, there's a description of them here:
https://en.wikibooks.org/wiki/MeGUI/x264_Settings

Thanks for your reply, i wil try learn.

[kiameliala]

Originally Posted by hello_hello

It's generally not necessary to mess around with individual settings too much. The rule of thumb is to use the slowest speed preset you can stand, which adjusts individual settings for you, along with the desired CRF value to specify the quality. The idea is that a given CRF value should give you roughly the same quality relative to the source each time (assuming all other settings are the same), but as CRF encoding aims to produce a certain quality, the encoder will use whatever bitrate is required to give you that quality, so the bitrate and file size can vary quite a bit from one encode to the next depending on how hard the video is to compress. Noisy or grainy video will require a higher bitrate than "clean" video. The alternative is to use 2 pass encoding to specify the bitrate/file size you want, but then you have no control over the quality. It also takes longer as CRF encoding only requires a single pass. x264 also has several tuning options to adjust some of the individual settings automatically for you. I use the film tuning for most encodes.

For the CRF value, the lower the value the higher the quality and the higher the bitrate. The default is 23, but most people probably use a lower value. The CRF value can also be adjusted a little according to the resolution of the video. As lower resolutions are generally upscaled on playback, it means any encoder artifacts are also upscaled, so if anything you might want to use a slightly lower CRF value for lower resolution video. I generally use CRF 18 for standard definition, CRF 19 for 720p, and CRF 20 for 1080p.

Something like this in the x264 command line would be adequate. A level of 4.1 ensures the encoder will adjust a few settings if necessary (according to the frame rate and resolution) to ensure the encoded video can be played by most hardware players. Level 4.1 is supported pretty universally these days.

--level 4.1 --preset slower --tune film --crf 18.0

If you want to start messing around with individual settings, there's a description of them here:
https://en.wikibooks.org/wiki/MeGUI/x264_Settings

--level 4.1 --preset slower --tune film --crf 18.0
I have used this setting but the output is still too big, 720p => 2.1GB

What i have to do? Thanks

[Rumbah]

Just increase the crf value, then the bitrate will decrease. If I remember correctly then an increase of about 6 will cut the bitrate in half.

[hello_hello]

Originally Posted by kiameliala

--level 4.1 --preset slower --tune film --crf 18.0
I have used this setting but the output is still too big, 720p => 2.1GB

What i have to do? Thanks

For CRF encoding, the final size is dependent on the duration in addition to the CRF value. What was the average bitrate? If your example is an average length movie, 2.1GB seems pretty reasonable to me, but try CRF19 or CRF20. Personally I wouldn't go any higher for 720p, but that's up to you.

Keep in mind though, you can't judge from a single encode because for a given CRF value the bitrate will change according to how hard the video is to compress. The next encode, assuming the resolution, duration and CRF value is the same, could result in a smaller file size, or it might end up larger.

The alternative is to use x265 instead, assuming it can be played by whatever hardware player you might be using. It's a lot slower than x264 though, and for x265 I do adjust some of it's individual settings as I find it blurs too much with the default values. For the same CRF value though, the bitrate should be lower, and you can probably get away with using slightly higher CRF values.

This is what I tend to use for a "slow" encode with x265, but everyone has different preferences. The bitrate will be greater than just using the slow preset on it's own. x265 doesn't have a film tuning, only tunings for heavy grain and for animation.

--crf 20.0 --profile main10 --preset slow --deblock=-1:-1 --no-open-gop --ctu 32 --rc-lookahead 40 --lookahead-slices 0 --psy-rdoq 1.5 --aq-strength 1.3 --no-strong-intra-smoothing --no-sao

[kiameliala]

Originally Posted by hello_hello

For CRF encoding, the final size is dependent on the duration in addition to the CRF value. What was the average bitrate? If your example is an average length movie, 2.1GB seems pretty reasonable to me, but try CRF19 or CRF20. Personally I wouldn't go any higher for 720p, but that's up to you.

Keep in mind though, you can't judge from a single encode because for a given CRF value the bitrate will change according to how hard the video is to compress. The next encode, assuming the resolution, duration and CRF value is the same, could result in a smaller file size, or it might end up larger.

The alternative is to use x265 instead, assuming it can be played by whatever hardware player you might be using. It's a lot slower than x264 though, and for x265 I do adjust some of it's individual settings as I find it blurs too much with the default values. For the same CRF value though, the bitrate should be lower, and you can probably get away with using slightly higher CRF values.

This is what I tend to use for a "slow" encode with x265, but everyone has different preferences. The bitrate will be greater than just using the slow preset on it's own. x265 doesn't have a film tuning, only tunings for heavy grain and for animation.

--crf 20.0 --profile main10 --preset slow --deblock=-1:-1 --no-open-gop --ctu 32 --rc-lookahead 40 --lookahead-slices 0 --psy-rdoq 1.5 --aq-strength 1.3 --no-strong-intra-smoothing --no-sao

Thank you, i will try this tips