Colour band on conversion

[sanlyn]

Good idea. I did that on one of the frames that had some pinkie left, but.....I guess the script was already running too slow. But it would be handy on one of those sections where there's only 1 or 2 of those frames.

[manono]

Thanks much. Now I can see it. It is ver. 2.1.1 I have installed. I went to install a newer version but it wanted me to restart my computer, which I'm not prepared to do at the moment. I now see my idea won't work all that well with this video. That stuff is all over the video. Something odd I noticed is that many of the frames are duplicates or phase shifted. Put on a bobber and notice all the dupes you get. This isn't any standard interlaced video and much of it is really progressive. And 15fps!

[DB83]

If you think the sound is LOUD then you shudda tried to listen to the first cap I did

Had I realised the issue with this particualr version of Huffyuv then I would have capped with Lagarith in the first place.

Also, although I set YUY2 in the capture, and no obvious settings in the codec, it still came out as RGB. Something seems a bit cookie there. Or that is another short-coming in my knowledge of colour-spaces.

[jagabo]

Also, although I set YUY2 in the capture, and no obvious settings in the codec, it still came out as RGB. Something seems a bit cookie there. Or that is another short-coming in my knowledge of colour-spaces.

When a codec is used to decompress a video there is a negotiation between the calling program and the codec to determine what colorspaces are supported by both and what colorspace is preferred. Even if a video is internally encoded as YUY2 this negotiation could lead to RGB being output by the codec. For example, Panasonic DV codec, works internally in YUV 4:1:1. But it always outputs RGB. The MPEG source plugin for VirtualDub will output YUV 4:2:0 by default. But if you set decompression format to RGB it will output RGB instead.

[DB83]

Also, although I set YUY2 in the capture, and no obvious settings in the codec, it still came out as RGB. Something seems a bit cookie there. Or that is another short-coming in my knowledge of colour-spaces.

When a codec is used to decompress a video there is a negotiation between the calling program and the codec to determine what colorspaces are supported by both and what colorspace is preferred. Even if a video is internally encoded as YUY2 this negotiation could lead to RGB being output by the codec. For example, Panasonic DV codec, works internally in YUV 4:1:1. But it always outputs RGB. The MPEG source plugin for VirtualDub will output YUV 4:2:0 by default. But if you set decompression format to RGB it will output RGB instead.

Cheers for that. Atleast it is not something that I have done this time.

[DB83]

Hmmn.

Should have looked at this before. Now, as I said, after running Part 1 the encode was 24 fps (originally 30 fps) and was in audio sync throughout the entire 40 minutes.

My test for Part 2 only covers the first 5 minutes but that is long enough for audio testing. True that the encode is now reported at 23.976 fps but that small difference appears to have screwed up the audio sync.

What gives here ?. Prepared to upload relevant samples of both.

edit: will obvoudly also check just that section but since there are other voice overs throughout this could be tricky to correct if the sync delay is not constant

[DB83]

Well I tested this on just the one minute sample that has visible audio - used vdub in stream copy mode rather than 'Trim' to create it from the Part 1 encode. That is in sync so not point in uploading that sample. So all I know right now that the shift, small but noticable, happens before or gradually over the 5 minutes.

I did look at both clips in vdub - the full first encode and the 5 minute second encode - and scence changes appear to happen on the same frame(s) despite the slight change in frame rate.

Gee. It may now be neccessary to build this up on a scene by scene basis.

[Tafflad]

OK .. pulling together collection of Plugin's listed.
Q ... as this is a new PC build, should I install 64bit AVISynth ... and if so will it work with all plugins mentioned ?

or do I need to stick with 32bit

The same Q for VirtualDub ... 32 bit or 64bit?

[sanlyn]

32-bit. Everything. Many filters won't work in 64-bit anyway.

The audio is imbedded with the sample avi youy posted. When it''s inverse telecined to 23.976 the adio is adjusted for the same fps. However, your audio capture is 44KHz -- non-compliant for DVD. I adjusted that to 48KHz in m encoder. Youy can adjust it in VirtualDub while one of the script runs by setting "Audio" -> "Full processing mode" -> "48000Hz" + "16-bit". Whether that affects the sync is anyone's guess. I couldn't tell from the 20-second clip.

[DB83]

Appreciate that the 20 sec sample is not ideal for audio as that was only intended for the colour issue per the OP.

I also accept that a change in frame rate, however small, should not affect the sync. Frequency should not, I would have thought, effect this since the original cap was 44khz and both the part 1 and part 2 encodes were also 44 hkz.

Seems I am on my own on this one but I will do some more tests on shorter video lengths.

[sanlyn]

You can adjust the audio sampling rate in a number of ways, but 44KHz isn't compliant with DVD/BD/AVCHD.

[DB83]

I know that. But that is not the issue. The first full-length vid (Part 1 of the script) is perfectly in sync throughout and at 44KHZ.

I ran another test. This time removing the FBI screen and the 'silent' titles but that is not in sync either. Methinks I will bite the bullit on this and encode the full vid (in reasonable sections) and see if the sync shift is constant - will not know that until the end of the vid.

I know that the OP is now crunching the numbers so the issue could be my system. If he also has issues with sound sync on part 2 then I can come back to this. This 4.08 minute intro is a little over 1 gig so too big to upload direct here. If I know someone will look at this I can upload it to a file-sharing site - multipart RAR. But before that I will, as time permits, encode the full Part 2 and attempt a manual re-sync.

What I was trying to establish is if there was anything in Part 2 of this script that could effect sound sync. The only obvious item is the swtch from 24 fps to 23.976 fps which I suspect happens in the line 'Assumefps...'. Yet I readilly accept with a perfectly muxed video and audio this should not affect sync. It is probably more a case of rogue frames in the original capture and if there are more of these later on........

[sanlyn]

AssumeFPS() adjusts audio and video at the same time if audio is imbedded in the source, and it is. Nothing in the scripts to change audio sync.

What are you encoding with that won't allow you to preview ahead to see what's happening? You should be able to do that with the nencoded AVI in a media plauyer to see if it's on track. In VirtualDub, it's often difficult to track. Do have OK sync in a media player with the AVI?

[manono]

The only obvious item is the swtch from 24 fps to 23.976 fps which I suspect happens in the line 'Assumefps...'.

I haven't looked at the video or the script but if the source is 24fps and you change the framerate with an 'AssumeFPS(23.976)' then that changes the video length and the audio synch unless you adjust the audio as well. It'll amount to over 3 seconds per hour and will become noticeable pretty quickly. After 3-4 minutes or so, maybe, depending on how sensitive you are to it? The obvious solution is not to use 'AssumeFPS(23.976)' in the script. Maybe there's a reason for it, but if for DVD you don't have to.

Edit: I've read sanlyn's post now. Even if the audio is in the AVI, the audio doesn't automatically get adjusted when using AssumeFPS. From the Assume page:

The AssumeFPS filter changes the frame rate without changing the frame count (causing the video to play faster or slower). It only sets the framerate-parameter. If sync_audio (which is false by default) is true, it also changes the audio sample rate to match the duration of the video, the pitch of the resulting audio gets shifted.

http://avisynth.nl/index.php/FPS

[sanlyn]

True, it's false by defauylt. OK, then, I noticed changing 24fps to 23.976 gave smoother motion in the "fastest" scenes. But forgot that sync_audio defaults to false. But fear not....

Create an avs script to open the Step2 Avi, or whatever complete AVI of the video your have so far:

AviSource("path\to\avi\complete.avi')
AssumeFPS("NTSC_FILM",sync_audio=true)

Open this script in VirtualDub. In VDub go to "Audio..."
- check "Full processing mode".
- Click "Audio..." again -> then click "Conversion..."
- set "48000KHz", "High Quality", and "16-bit" if not already set.
- Click "OK".
- Click "File..." -> "Save WAV..."
Give the audio file a name with a .wav extension, as in "NewAudio.wav", and pick a location. Then "Save".

When you encode the full video, specify this .wav file as the source audio. If you plan to change the size or number of frames in your video, then imbed the new .wav file into your AVI in this manner:

After you create the new .wav file:
With the "complete" avi loaded in VirtualDub:
- Click "Audio..." -> then "Audio from another file..."
- Locate and select the new .wav source you just created, then click "Open".
- Click "Audio..." -> "Direct stream copy"
- Click "Video..." -> "Direct stream copy"
- Click "Save AVI..." and save with a new .avi name and location.
This should run at least twice the fps of the video, maybe even 3x the frame rate.
If you don't want the old AVI with bad sync, remove it or archive it.
The change from 24fps to 23.976 is 0.01%.

You can also do it in Audacity, but more complicated. Audacity seems to despise the use of whole numbers or decimals. Always wants percentages. Bummer.

[DB83]

@Sanlyn

Many thanks for your continued interest in this little project

@Manono

Muchas Gracias for your most valuable input.

Followed the instructions to the letter on just the 4 minute intro and......

....... sound is now backin sync. Bet you can hear that hugh sigh of relief

I do not quite understand with what you mean by 'Previewing ahead'. I am using vdub, without the script, to set markers (or later to determine frame numbers for the 'Trim'). Media Player is used to preview the original clip and review the encoded clip.

[sanlyn]

By "encoder" I mean the app that encodes AVI -> MPEG2. Of course, if you play the AVI in any player (I've been using MPC or MPC-BE mostly) you can preview back and forth to check audio before encoding. Most of my encoders have preview and edit screens for the same thing.

[DB83]

Ah. Not got to that stage yet with the currect scripts. I did create a test dvd using the original full-length vid using avstodvd.

Essentially though, I regard myself here as the 'Beta Tester' for the OP as I have a little more experience with digital video just to establish any issues (like the audio now thankfully solved). I do not need a dvd of this myself but again, if neccessary, guide the OP through the process.

[sanlyn]

I often use that routine to make a "master .wav" for a VHS capture when making a IVTC'd Lagarith AVI "working copy" of the original huffyuv or Lagarith capture (the original gets archived to external HDD). The working copy gets cut into 3.5 GB sections, and each of those gets cut into maybe a dozen smaller clips. That's just for the important stuff in horrible shape. All of my "good" old movie tapes have been transferred already or replaced with commercial DVDs.

[Tafflad]

Guys .. just to confirm, although on full 64bit PC I installed 32bit AVIsynth & Virtual Dub .... had interesting time getting all plugins together.
But Pass1 carried out .... 29fps 40min

[Tafflad]

Essentially though, I regard myself here as the 'Beta Tester' for the OP

and that is much appreciated

[Tafflad]

Guys all steps followed, and after some SoundForge work on the audio, have created the DVD.
Very pleased with results, thanks for your help & explanations.

Also big thanks to DB83 for the extra help & walking thru the steps.

[DB83]

A happy 'customer' at last

Methinks I can now bin that 50+ gig of captures, recaptures, encodes, test dvds, empty bottles of JD, asprin etc. etc.

But 'living' with that footage for the last few weeks has encouraged me to pop along to Sports Direct and pick up their last kneeboard. Now all I kneed to do is requisition a sheep to tow me down the Taff as I sing the refrain from 'Cwm Rhondda'. Back-flips, 360's, traction. Here I come.