[MEncoder-users] Is it possible to do IVTC on video from the HD-PVR?

[Laine Lee]

On 5/29/10 3:53 PM, "Andrew Berg" <bahamutzero8825 at gmail.com> wrote:

> I recorded a show with the HD-PVR that I know was recorded at 24p and
> telecined to 30i for broadcast. I have a working command line for shows
> for deinterlacing 30i content (most of what I record is originally
> recorded at 30i):
> 
> mencoder in.ts -demuxer lavf -fps 60000/1001 -ofps 30000/1001 -of avi
> -oac copy -ovc x264 -x264encopts [x264 options] -vf
> yadif=1,framestep=2,harddup -o out.avi
> 
> I've tried various combinations of -fps/-ofps values and filmdint=io=
> values with no luck. Someone on this list provided a script to determine
> if a video is telecined, and according to it, these videos are not
> telecined:
>> Detecting telecine'd content
>> #  of telecine'd frames detected in a ~1 second sample of video
>> at various offsets:
>> # 0 x -62348618 = 0: 0
>> # 1 x -62348618 = -62348618: 0
>> # 2 x -62348618 = -124697236: 0
>> # 3 x -62348618 = -187045854: 0
>> # 4 x -62348618 = -249394472: 0
>> # 5 x -62348618 = -311743090: 0
>> # 6 x -62348618 = -374091708: 0
>> # 7 x -62348618 = -436440326: 0
>> # 8 x -62348618 = -498788944: 0
>> # 9 x -62348618 = -561137562: 0
>> # 10 x -62348618 = -623486180: 0
>> # 11 x -62348618 = -685834798: 0
>> # 12 x -62348618 = -748183416: 0
>> # 13 x -62348618 = -810532034: 0
>> # 14 x -62348618 = -872880652: 0
>> # 15 x -62348618 = -935229270: 0
>> # 16 x -62348618 = -997577888: 0
>> # 17 x -62348618 = -1059926506: 0
>> # 18 x -62348618 = -1122275124: 0
>> # 19 x -62348618 = -1184623742: 0
>> TOTAL=0
>> TARGET=290
>> TELECINE=false
> Perhaps the script doesn't detect telecine and normal IVTC is impossible
> with these videos because the capture is analog-to-digital, but it can't
> hurt to see if someone knows a way. Looking around on Google, someone
> suggested using Avisynth's TDecimate(), but I need to do these
> transcodes on a Linux box, so Avisynth isn't an option. decimate or detc
> may be useful, but I don't know how I would configure them to fit this
> situation.

You should be able to play the output of the HD-PVR in recent versions of
MPlayer. You can see telecining yourself by viewing frame by frame with the
"." key. I have to use "-demuxer lavf" and give playback just a moment to
stabilize before pausing and advancing a frame at a time with ".". If in
roughly every 12 frames you see 6 pairs of duplicates, 2 consecutive pairs
of which look like a double-exposed photo with combing, you've got a 60 fps
telecined, interlaced source. That's all that the HD-PVR knows how to output
to my system, but my system is not what typical MEncoder and MPlayer users
have.

Can you make a clip available?

Laine Lee