Best tool for Inverse Telecining and deinterlacing ?

Question

I have very limited experience in encoding videos before.
Recently I'm trying to transcode a DVD into H.264 with x264. All the VOB files are dumped already.
As for the video part, I've decided to do it this way :
mkfifo TEMP.y4m
x264 OPTIONS -o OUTPUT.mkv TEMP.y4m & mplayer -vo yuv4mpeg:file=TEMP.y4m OPTIONS INPUT.VOB
I believe this method to be clean and efficient.
The problem is: This VOB file is in NTSC format, and I'm pretty convinced that it's telecined, after reading this:
http://www.doom9.org/ivtc-tut.htm wrote:TELECINE is a process where the FILM first is slowed down to 23.976 frames/second. Then for every 4 frames, an extra frame is created from fields of adjacent frames. If a frame consists of two fields, top (t) and bottom (b) and the original sequence is 1t1b 2t2b 3t3b 4t4b, then the telecined sequence would be 1t1b 2t2b 2t3b 3t4b 4t4b (commonly called 2:3 pull down because of the alternating 2 field, 3 field progression). This also means that the frame rate increases to 29.97 frames/second.
I viewed the video frame by frame, and found out that there're 2 sequential interlaced frames out of every 5 in a non-static scene. These are 2t3b 3t4b frames I think.
mplayer comes with some video filters that might help: With "-vf pp=" the result isn't that satisfying, but "-vf pullup" do the job nicely, that is, I can almost see no interlacing at all with this command:
mplayer -vf pullup VTS_01_1.VOB -noconfig all
On the other hand, I also noticed that there're 2 sequential repeated frames out of every 5 in a non-static scene. The frame-rate is 29.970 fps. This is bad because repeating means inefficiency in terms of compression. The better result is using only one of these 2 repeated frames at a frame-rate of 23.976 fps, which means dropping 20% extra frames.
But I don't know how to achieve this.
I want to achieve this at the mplayer decoding stage, so that x264 is fed with a yuv4mpeg source stream with no interlacing or extra frames.
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I'm not familiar with mencoder's options, though it seems to be able to drop the extra frame with "-vf pullup,softskip -ofs 24000/1001", but I can't find a way to let mencoder output as yuv4mpeg. Also there is a reason why I tend to avoid using mencoder:
mencoder -ss 209 -endpos 20 -ovc copy -oac copy -o _short_.vob VTS_01_1.VOB
This is supposed to cut a 20-second short clip from the VOB using copy. But even task as this simple could be wrong...which is really disappoiting. Look at these 2 screen shots.
By using mencoder -ovc copy::
http://omploader.org/vMjE3Zw
The original (mplayer VTS_01_1.VOB)::
http://omploader.org/vMjE3aA
Maybe it's just my build of mencoder(compiled at home)... But with this I really can't say mencoder is to be trusted.
...Or, is it something wrong in my command?
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By the way, for this specific DVD, I believe mplayer plus x264 together can achieve the best result; on the other hand, just as the title suggests, I'd like to find some decent tool to do IVTC and Deinterlacing. CLI preferred but good GUI apps are also welcome
Thanks in advance!
Last edited by lolilolicon (2009-07-25 03:31:59)

Answer 1

skottish wrote:You should be able to use the -vf pullup,softskip stuff still.
man mplayer wrote:Softskip
Only  useful  with MEncoder.  Softskip moves the frame skipping (dropping) step of encoding from before the filter chain to some point during the filter chain.  This allows filters which need to see all frames (inverse  telecine,  temporal  denoising,  etc.)
Actually, when I tried::
mplayer -vf pullup,softskip VTS_01_1.VOB -noconfig all
The result is the same as just using "-vf pullup". The extra frame can't be dropped by mplayer this way......
Too bad many "convenient" tools like h264enc all use mencoder. I don't know whether handbrake does too. Haven't tried it out.
Avisynth is a great tool but works only for windows. x264's built in deinterlaced mode does no good in my case. ffmpeg's filters are still too limited by far. What can I do? Is there anything that does nothing but good IVTC?
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Klepper wrote:It says to always use the softskip filter together with pullup
man mplayer wrote:Always  follow  pullup  with the softskip filter when encoding to ensure that pullup is able to see each frame.
In my case, pullup seems to work better than filmdint: I've just tried the h264enc script which is almost totally a frontend to mencoder. Look at the mencoder filters it used:
mencoder VTS_01_1.VOB -o 01.avi -fps 30000/1001 -ofps 24000/1001 -vf filmdint=fast=0/io=30:24/dint_thres=256,softskip,harddup -oac pcm -ovc x264 -x264encopts <x264OPTIONS>
See, it also used filmdint as you suggust. The result is not too bad: removed the extra frame and plays at 24fps. But I can still notice interlacing occasionally. Maybe it's because the video isn't constant pattern "PPPII" but with some shifting (say, PPPIIPPPII...PPPIIPIIPPPIIPPPII, I found some pattern like this in the source VOB)
Man page says "io=<ifps>:<ofps>" must match "-fps/-ofps" ("-fps 30000/1001" and "-ofps 24000/1001" in my case.)
Since -ofps is an option ONLY for mencoder, but not for mplayer, filmdint can't make mplayer drop the extra frame like mencoder.
I played the VOB with "mplayer -vf filmdint=fast=0/io=30:24 VTS_01_1.VOB -noconfig all" and there're lots of "@@@@@@@@ Bottom-first field??? @@@@@@@@" spitted out in the console. I read about this in the man page but don't understand....
If the source is MPEG-2, [u]this must be the first filter to allow access to the field-flags set by the MPEG-2 decoder[/u]. Depending on the source MPEG, you may be fine ignoring this advice, as long as you do not see lots of "Bottom-first field" warnings.
I don't have any other filters in the command line, so... why?
The occasional interlacing is the same as the video encoded with h264enc. Also, it did not drop the extra frame anyway.
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Also I have a doubt:
In my first post, I wrote:
The original (mplayer VTS_01_1.VOB)::
http://omploader.org/vMjE3aA
But I think even this is not "original" -- not as good as the original video before it was telecined into NTSC format. I think it's mplayer not doing it good enough. The real original frame should have no blocking......
I've compared it to one fansub rip, the same frame looks better than in the image above, very little blocking, also the bass string isn't blurred like in the image above:
http://omploader.org/vMjE5aw
I don't know how they did it. And I actually want to do it better
Last edited by lolilolicon (2009-07-25 09:32:30)