Frame Jump Every Second With Deinterlace ?

[blewyn]

I'm converting 1920x1080 59.94i footage to 1280x720 59.94p. It's MP4 video from a Sanyo Xacti HD1000 camera. I do this :

a) MP4 to AVI with MP4Cam2AVI program.

This gives me an interlaced 59.94fps file which, when opened in VirtualDub, seems to be a 30fps interlaced file which has a duplicate for every frame. As you key through it frame-by-frame, every 2nd frame is a duplicate, so I :

b) save as lagarith codec file, processing every 2nd frame only

This makes a 29.97fps lagarith file. I then :

c) save as lagarith again, this time using the bob doubler filter to deinterlace and double fps back up to 59.94.

This works fine, except for one thing. Every 60th frame is in fact a copy of frame 58, and there seems to be a frame missing between 61 and 62..

Can you help ?

[jagabo]

Why don't you open the MP4 file directly in VirtualDub and apply the Bob Doubler filter? Or even better, the Deinterlace/Yadif/double_frame_rate filter.

[blewyn]

Because VirtualDub won't accept an MP4 file - it has to be converted to AVI first.....?

[jagabo]

Get the MP4 or DirectShow source plugins and you can open MP4 files directly in VirtualDub. You might also need VFW decoders for the audio and video. ffdshow should work for that. I can open Xacti files, no problem.

[blewyn]

Where do you find the "mp4 or directshow source plugins" ?

I tried Yadif>double frame on the 29.97 interlaced lagarith file and the same thing happened....frame 60 is a copy of 58, 61 is a copy of 59 and there'a a jump (presumably because the real 60 and 61 are missing) when you key over to frame 62...

[jagabo]

The VirtualDub page here links to the source plugins. See the section entitled "Import plugins:".
https://www.videohelp.com/download/VirtualdubPluginPack.zip

[blewyn]

The probem wasn't in the bobbing - it's in the decimated file (the 29.97 interlaced lagarith file). Each 30th frame is a copy of the 29th......I checked the original file and there are no duplicates at 60th frame...

[jagabo]

a) MP4 to AVI with MP4Cam2AVI program.

This gives me an interlaced 59.94fps file which, when opened in VirtualDub, seems to be a 30fps interlaced file which has a duplicate for every frame. As you key through it frame-by-frame, every 2nd frame is a duplicate

It sounds to me like MP4Cam2AVI is screwing up your video. If there are no duplicate frames in your source there should be no duplicate frames in the AVI. And the frame rate should be exactly the same. Note that 59.94i is the same thing as 29.97i. Marketing just decided the bigger number sounds better. Post a short sample of your source and the AVI from MP4Cam2AVI.

[blewyn]

Thanks for the link !!

[jagabo]

I have better luck with the DirectShow plugin. You need to have a DirectShow MP4 reader and codecs installed though.

[blewyn]

I installed the MP4 plugin and now VirtualDub accepts the Sanyo *.MP4 files, but all I see is a black screen, no picture. Any ideas ?

[blewyn]

How can I make a small chunk of *.MP4 file for upload ?

[jagabo]

On the Open File dialog, use the little pulldown at the bottom and select DirectShow (assuming you installed the DirectShow plugin too). See if that works. You can also try ticking the "Ask for extended options..." option and see if there are any parameters you can adjust (some input plugins don't have extended options).

You can extract a small clip with AviDemux. Use the Mark-in (A), and Mark-out (B) buttons to mark a short segment, set Format to MP4, then Save. Be sure to add .MP4 to the filename, AviDemux doesn't automatically add extensions.

[blewyn]

Thanks !! Will get on that now. I checked the AVI file made by MP4Cam2AVI frame-by-frame and there is no hiccup at frame 60...each 2nd frame is a duplicate, and interlaced. When I process to a decimated 30fps interlaced file, frame 30 is a copy of frame 29 and there is a jump to frame 31, indicating that the original frame 30 is missing.......I amusing "decimate by 2" not setting a target FPS.

[poisondeathray]

It sounds to me like mp4cam2avi is causing problems if there are duplicate frames

Maybe you could post a native sample .mp4 , you could also use yamb to split a section

[jagabo]

Yes, it makes no sense that the AVI from mp4cam2avi repeats every frame.

[blewyn]

Here's a couple of pieces of the footage - one native from the Sanyo camcorder (1920x1080 mode 59.94i) and the other after MP4Cam2AVI conversion.
When I open the MP4 file with the directshow plugin (I found version 0.5 ?) I just get a black screen....?

[jagabo]

Why is your AVI file called "chunk of mp4.avi" and the MP4 file called "same chunk after mp4cam2avi.mp4". I thought your source was MP4 and mp4cam2avi converted it to AVI?

[blewyn]

Bugger. Named the files the wrong way round....sorry about that. The *.MP4 file is the original.

[blewyn]

Managed to get the MP4 file loaded into VirtualDub using Phaeron's latest Directshow plugin from the thread on the forum - it looks like it too has duplicate frames ?

[blewyn]

The MP4 version maxes out my CPU in VirtualDub and although it will step through the video slowly, when I press play it says "The decompression codec cannot decompress to an RGB format. This is very unusual. Check that any "Force YUY2" options are not enabled in the codec's properties."

When I select File > Information nothing happens, and GSpot just gives me "codec status undetermined". So I'm not sure which codec to check in ffdshow......? MPC's file properties tells me MPEG4 Video (H264)

[jagabo]

Yes, I tried the DirectShow plugin and it's missing frames or fields. The QuickTime plugin worked when I used the extended options section to select Movies Task or ICM Decomp. I have QuickTime Alternative v1.81 installed. The output from Quicktime was already bob deinterlaced at 60.485 fps. The file converted to 704x400 Xvid/MP3 AVI is attached. Note that VirtualDub does not handle HD colors (a rec709 vs rec601 problem) correctly so the colors are slightly off.

[poisondeathray]

yes, that mp4cam2avi software is introducing bad frames

how did you cut the mp4 sample? it's damaged - maybe that's why it's having problems loading ?

you can load it through avisynth correctly , if you trim the bad frames off. (and if you have proper directshow splitters and decoders installed)

I encoded this to xvid/mp3 (but you can use vdub or any encoder that accepts avisynth scripts)

DirectShowSource("same chunk after MP4Cam2AVI.mp4")
AssumeFPS(30000,1001)
Yadif(1,1)
LanczosResize(1280,720)
Trim(0,240)

[poisondeathray]

The framerate is incorrectly flagged as 59.942 (should be 29.97)

The output from Quicktime was already bob deinterlaced at 60.485 fps.

Interesting. I have qt pro installed and it open the files with 59.942 with the qt plugin (ICM decomp) for vdub, but is still interlaced

[jagabo]

DirectShowSource() isn't working right for me. It's giving a 25 fps frame rate. The video has the right running time but it ends prematurely. Ie, it's missing the last 1/6 of the frames and playing the first 5/6 at 25 fps instead of 30 fps. Of course, we all know DirectShowSource() is at the mercy of installed source filters and codecs.

ffdshowsource2() didn't work right either. There were missing frames.

[poisondeathray]

DirectShowSource() isn't working right for me. It's giving a 25 fps frame rate. The video has the right running time but it ends prematurely. Of course, we all know DirectShowSource() is at the mercy of installed source filters and codecs. Ie, it's missing the last 1/6 of the frames and playing the first 5/6 at 25 fps instead of 30 fps.

ffdshowsource2() didn't work right either. There were missing frames.

yes, directshowsource() is going to depend on your system filters - it seems to be working ok for me


I suspect some of the inconsistencies were caused from cutting the file a certain way. I found some other video samples from the same camera in another thread, and they behave "normally" (except for the incorrect 59.94 fps)

Note that VirtualDub does not handle HD colors (a rec709 vs rec601 problem) correctly so the colors are slightly off.

actually there is more to this, it's the well known "quicktime gamma shift bug" - it you decode h.264 through quicktime, everything will look brighter (it's not just 1.8 gamma vs. 2.2 gamma, there is a bit more than that). You can compare the file I uploaded

[jagabo]

yes, directshowsource() is going to depend on your system filters - it seems to be working ok for me

What h.264 decoder are you using? I'm using ffdshow.

Thanks for the info about QTSource's gamma problems.

[poisondeathray]

yes, directshowsource() is going to depend on your system filters - it seems to be working ok for me

What h.264 decoder are you using? I'm using ffdshow.

ffdshow as well, but nero mp4 splitter (<= for some reason it hotlinks to haali, but I really mean nero)

[poisondeathray]

Thanks for the info about QTSource's gamma problems.

... there's actually a lot more problems than the gamma shift bug - decoding through quicktime adds noise (perhaps meant to be a dither?) and decodes chroma a lot "blockier". This has been confirmed on several forums, frequently noticed by people trying to pull greenscreen keys . Even other formats like MPEG2 (XDCAM) and DV decode significantly worse (blockier) through quicktime - even on a MAC



e.g. (QT used on the left, ffmpeg was used on the right)

http://i55.tinypic.com/29y2m51.png

[jagabo]

Yeah, I normally don't have Quicktime installed. I forget why I installed it recently. Got rid of it and am now using Haali+CoreAvcPro. DirectShowSource("file.mp4", fps=29.97) is working properly. Haali+ffdshow is working too.