Selur's Little Message Board

I changed --bluray-compat to --aud. It works as well.
TMGNEC settings showing:
"Adjust the stream structure for BluRay – enabled"
 
If –aud works, should this be preferred?
 
Re.:
"x264->Base->Restriction Settings->AVC Profile/Level" to "High/4.2" - Level 4.2 has to be used for 1920x108050p/60p per Blu ray specs
"x264->Misc->Main->Restrictions->Access unit delimiters"
"x264->Misc->Main->Restrictions->Contrained intra prediction"
limit B-frame usage to max 3 - It was suggested by TMPGEnc
"x264->Base->Restriction Settings->Multi-slice->restricted by slices per frame" 4
only use b-pyramid 'disabled' or 'strict'
 
From TMPGEC web:
"Enabled, and sets the type, of the B frame reference mode. This option improves the output image quality by allowing the reference to B frames within a GOP instead of just I or P frames, but also increases the player's workload, possibly limiting the outputted file's player support. The [Strict] setting uses the same method as the Blu-ray standard." This setting is available when the [Maximum Number of Reference Frames] setting is 4 or more (or "0 Automatic" ) and [Number of B Frames in GOP] is 2 or more in the [GOP] tab.
 
 "x264->Base->Restriction Settings->signal hrd" to "vbr"
no more than 6 references
"x264->Frames->GOP size min/max" to 1 and 50 or 60. GOP max exceeding 50 or 60 makes encoded file not complaint. From TMPGEnc clip checker:
Max Number of GOP Fields = 100 Field (for 50fps)
]limit VBV to "BD 25/50 1x" 25000/25000
 
TMPGEnc from encoder parameter as a target showed VBV Buffer Size = 3213 kB, exceeding this makes a not compliant file
 
"x264->Frames->Weigthed P-frame prediction" with 'refs' or disabled'

Tested to add  "--aud --constrained-intra":
"x264->Misc->Main->Restrictions->Access unit delimiters" -> adds '--aud'
"x264->Misc->Main->Restrictions->Constrained intra prediction" -> adds '--constrained-intra'
It works with dev_2021.03.12 update.
 
They are not added next to each other and not at the beginning.
Command Line:
 
x264 --bitrate 22500 --profile high --level 4.2 --ref 4 --keyint 50 --min-keyint 1 --scenecut 40 --bframes 3 --b-bias 0 --b-pyramid normal --direct auto --b-adapt 2 --sync-lookahead 12 --ratetol 2.0 --cplxblur 20.0 --qcomp 0.60 --qblur 0.5 --mbtree --rc-lookahead 25 --ipratio 1.4 --pbratio 1.3 --chroma-qp-offset 0 --slices 4 --qpmin 0 --qpmax 69 --qpstep 4 --partitions i4x4,i8x8,p8x8,b8x8 --8x8dct --me umh --merange 16 --mvrange -1 --subme 9 --cabac --trellis 2 --psy-rd 1.00:0.00 --weightp 1 --aq-mode 1 --aq-strength 1.00 --vbv-maxrate 22500 --vbv-bufsize 24000 --nal-hrd cbr --aud --nr 0 --deadzone-inter 21 --deadzone-intra 11 --cqm flat --threads auto --sar 1:1 --qpfile GENERATED_QP_FILE --deblock 0:0 --non-deterministic --constrained-intra --range tv --colormatrix bt709 --demuxer raw --input-res 1920x1080 --input-csp i420 --input-range tv --input-depth 8 --fps 50/1 --output-csp i420 --output-depth 8 --output "C:\Users\xxxx\AppData\Local\Temp\--aud --constrained-intra_test.264" -

Reading:
source: https://help.pegasys-inc.com/en/tmsr5/10011.html

it looks like VBV Buffersize allows higher values.

Cu Selur

They send this link after I found values on their SW tool, it was working.
Team work  

I just tested VBV Buffer Size = 28000 kbit (as they specify max Buffer size 3500000 bytes).
Set encoding Average Bitrate (1-pass) to = 25000 kbit/s.
It works.

What is the safe value for VBV Buffer Size, how close it can go to max 28000 kbits?

Quote:What is the safe value for VBV Buffer Size, how close it can go to max 28000 kbits?

Unless x264 is broken 28000 kbit should be a save value.

Quote:Set encoding Average Bitrate (1-pass) to = 25000 kbit/s.

probably a bad idea, when the maximum bitrate is 27 150kbps (video+audio+overhead). Also 1pass encoding usually is always a bad idea,...

Cu Selur

Encoding Average Bitrate (1-pass) was only experiment, to check if settings work, it is fast and I can control the bitrate, again for an experimental purpose.

Also tried VBV Buffer size above max limit, 28100, resulted in none compliant file.

For actual encoding I am using Specific Filesize/bitrate (2-pass) 22Mbps-24Mbps at max, adding AC3 2ch audio at 224kbits/s makes safe enough below 27150 knits/s. Is this range 22Mbps-24Mbps safe enough?

For similar bitrate with CRF need to set CRF = 12 -14 for my VHS transfer.

I like Specific Filesize/bitrate (2-pass) more over CRF as it lets control the bitrate.

If I set encoding Specific Filesize/bitrate (2-pass) = 24000 kbits/s, should I set VBV Buffer size 24000, or get higher more close to max 28000?

If you properly set VBV Buffer and VBV Max Bitrate to the maximum allowed values everything should be fine assuming the container overhead isn't too bad.
With such high bit rates and m2ts container overhead should be 5%. so you should be fine with your settings.
crf will be increased by x264 if necessary to comply to the vbv restrictions.

Cu Selur

What is correct "Signal HRD" value:
X264>Base> Restriction Settings> Signal HRD (check), vbr or cbr?

By default for BluRay it is set as cbr, I read that for BluRay it is nalhrd=vbr:
https://forum.doom9.org/showthread.php?p...ost1399419

Blu-ray iirc should support both cbr and vbr.
But you are right the default should be vbr is more efficient regarding bit rate contribution.

Cu Selur

I accidentally learned that "Signal hrd" has to be enabled, cbr or vbr set, "--nal-hrd vbr" added to the Command Line, otherwise it results in VBV Buffer size and Max Fill rate values exceeded the ones that are set, and makes none AVCHD 2.0 compliant file.