Handbrake Distortians - Need Help

[wkan0]

Have many Humax TV recordings which are 1920x1080 PAL, Interlaced, H.264 *.ts files, with variable bitrates around 12 Mbit/s, which I want to convert with Handbrake to smaller *.mp4 files without loosing too much quality.

Did an initial Handbrake test, with a 49min video, which went well, but did notice 3 destortians in the mp4 output file. These distortians only last a second or so, but are very noticeable, lots of blocks are on the screen (e.g. see uploaded image). Did check these specific timeslots in the source file, frame by frame, but they all look ok.

Have extracted these particular small parts from the source file to another *.ts file, and did numerous Handbrake test against it, with all kind of settings and filters, but I am not able to get rid of the distorations. Even tried RF=0, Preset=Placebo, but didn't help. Since the input file is Interlaced, tried some Filter settings like Decomb Bob/Default, but the distortians stay.

Please advise, since I am not an expert, and am using Handbrake for the first time. Thanks!

Below the MediaInfo of the small source file (with the 3 extracted problem areas):

Format : MPEG-TS
File size : 36.0 MiB
Duration : 22 s 254 ms
Overall bit rate mode : Variable
Overall bit rate : 13.6 Mb/s

Video
ID : 2001 (0x7D1)
Menu ID : 19401 (0x4BC9)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, RefFrames : 4 frames
Codec ID : 27
Duration : 21 s 920 ms
Bit rate : 11.9 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan type, store method : Separated fields
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.230
Stream size : 31.2 MiB (87%)
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709


[Attachment 44397 - Click to enlarge]

[sneaker]

1. try HandBrake nightly
2. try QuickSync decoding (If available on your system. Sometimes error concealment is better on hardware decoders.)
3. remux to mkv using mkvtoolnix and try again
4. report to HandBrake team https://github.com/HandBrake/HandBrake/issues

If you want anyone here to comment further upload the file.

[wkan0]

Attached my source file which contains only the three problem scenes. When converting with handbrake, the following three distorations appear in the target *.mp4 file
1. Part of the Waterfall scene
2. Red roof combing effects (was also in the source file, but would like to eliminate it).
3. Person walking away from the bear.

[sneaker]

1./3. Seems to be a known problem:
https://forum.videohelp.com/threads/383215-Why-in-Handbrake-Not-in-Any-video-Converter
https://github.com/HandBrake/HandBrake/issues/674

It should work in Handbrake nightly.


Maybe someone else can recommend a filter for 2.

[wkan0]

Just installed Handbrake Nightly (HandBrake-20180114-96909e4_x86_64-Win_GUI.exe), as recommended, and indeed the distortians have dissapeared. Thanks for the solution!

Would like to understand what kind of fix is in the Nightly build since, although I am not an expert, always thought that Handbrake is just a frontend to the x264 encoder, which it invokes with certain parameters, based on what is defined on the input screens. Does the nightly build invoke another version of x264 or are different parameters passed to it? Or perhaps something else?

Only issue left is the distortian in de Red roof scene. Are these Moire patterns? And, how can I elinimate them?

[sneaker]

The issue is not on the encoding side (x264) but on the decoding of the source. Decoding is not done by x264.

[wkan0]

Just enabled Intel Quick Sync Video (QSV) and used it in Handbrake (as proposed 2nd solution) and it also solves the problem.

Have an Intel Ivy bridge processor (i7-3770), so not the latest QSV version, but was still amazed by its speed, although I realize that output quality isn't as good as using the Handbrake higher quality settings.

Since I was impressed by the QSV speed and have lots of Humax TV recordings (1080i) to convert, have some questions:
1. Would like to to know to which Handbrake quality settings (e.g. Preset / RF= / Encoder Preset), Intel Quick Sync is comparable to? Just to have a rough idea.
2. Did see that the output file was High/4.0 with a bit-rate of 11.6 Mb/s. The bit-rate is almost the same as the source file, so I don't seem to gain anything related to file size (which I wanted). Is it possible with QSV to reduce the size of the output file in some way?
3. Is the QSV enhancement in the latest Intel processors worth the upgrade?

[jagabo]

2. Did see that the output file was High/4.0 with a bit-rate of 11.6 Mb/s. The bit-rate is almost the same as the source file, so I don't seem to gain anything related to file size (which I wanted). Is it possible with QSV to reduce the size of the output file in some way?

File size = bitrate * running time. So you create a smaller file by using a lower bitrate or a higher QP. Quality will suffer, of course.

Regarding your moire/strobing problem on the red roof: a strong NLMeans filter in Handbrake will help. But you may not care for what it does to the rest of the picture. And it will slow you down by quite a lot. AviSynth has VInverse() which handles it pretty well (basically burring away the moire artifacts without damaging the rest of the video) and is pretty fast but it's doesn't work with Handbrake (you'd have to use another encoder like QSVEncC, MeGUI, or the x264 CLI encoder) and has a steep learning curve.