How to drop 1 frame every 25th frame >>> plzz help

[kartikoli]

i want to drop frame of a movie which has 25FPS so that it becomes 24fps (decreasing the total length of an video stream)then i will slightly change the FPS in time code to make it 23.976 exactly

so my question is can i do it without re encoding the video stream with the help of time code in mkvmerge or in any other application

if possible
1:- timecode to drop frame every 25th frame
2:- timecode to convert 25FPS to 24FPS [i was using it sometime bak but now lost the timecode text file]

[Ghitulescu]

If your video is an AVI/MKV having DV or M-JPEG video, then yes, it's possible.

[kartikoli]

yes its h264 in mkv container .... tried vdubmod but it keep on crashing

[manono]

i want to drop frame of a movie which has 25FPS so that it becomes 24fps (decreasing the total length of an video stream)
That makes no sense. If you change it to 24fps without dropping any frames, the length of the film increases, not decreases. And the audio goes out of synch unless you reencode it to the longer length. If you change it to 24fps by dropping one frame in 25, the video becomes jerky playing because of one missing frame every second, and the length remains exactly the same. The only thing that decreases is the total frame count, not the length.

VDubMod doesn't support h264 or MKV.

[sneaker_ger]

@manono

You're assuming that a "proper" speed-up has been made or that it's "real" 25 fps material. But it could also be that the 24->25 conversion has been done by inserting an extra frame every second. If latter is the case it should be possible to do what he plans by manipulating the timecodes.

[manono]

@manono

You're assuming that a "proper" speed-up has been made or that it's "real" 25 fps material. But it could also be that the 24->25 conversion has been done by inserting an extra frame every second. If latter is the case it should be possible to do what he plans by manipulating the timecodes.
Yes, I am assuming that. Conversions on retail DVDs done by adding a duplicate frame every second are so rare as to be not worth mentioning. And even if that were the case, I know of no way to remove them without reencoding. I don't know anything about manipulating timecodes. Is it possible to choose which one-in-every-twenty-five-frames to drop?

And my other point still holds; he said the length would decrease, but that's not true.

[sneaker_ger]

Yes, you can set the time when to show a frame (and thus also which to skip).

But I agree that this method is nonsense for the vast majority of sources and that his explanations are kind of vague (to say the least), as doing 25->24 wouldn't decrease the length (of time). Maybe he meant length as in "number of frames"?

[Nick]

I suspect this is another angle on the problem in the OP's other current thread (http://forum.doom9.org/showthread.php?t=154483). Having failed to get satisfactory results lengthening an audio stream to match the video, attention has now moved to altering the video to fit the audio. If this is the case, I personally think messing with the video is futile and if not, I am neither sure what the OP is trying to achieve, nor whether the method outlined in this thread will actually ever achieve it.

[sneaker_ger]

Well, at least his threads are in the correct section ... :rolleyes:

This is really getting confusing. He should explain better and actually follow the advices given to him...

[Ghitulescu]

If your video is an AVI/MKV having DV or M-JPEG video, then yes, it's possible.

yes its h264 in mkv container .... tried vdubmod but it keep on crashing

Ok, then now it's the perfect time to learn about inter-frame and intra-frame codecs.

[sneaker_ger]

Learning doesn't hurt, but you can skip frames in Matroska no matter the format because of the timecodes.

[setarip_old]

@kartikoli

(I guess it's okay for me to respond since two moderators have posted to this thread)

i want to drop frame of a movie which has 25FPS so that it becomes 24fps (decreasing the total length of an video stream)then i will slightly change the FPS in time code to make it 23.976 exactly...its h264 in mkv container

Try loading the file into "tsMuxerGUI", highlight the videostream and change the fps to the equivalent of 23.976fps (24000/1001).

Save as "BluRay" (Should take about 5 minutes)

Load BluRay "package" into MakeMKV and save as MKV...

[sneaker_ger]

Or simply do it in one step using mkvmerge GUI. (Or does tsMuxer do anything in a different way?)

[setarip_old]

Or does tsMuxer do anything in a different way?If nothing else, the combination of tsMuxerGUI and MakeMKV should be faster...

[sneaker_ger]

Really? It would really surprise me, as you'd have to write a bit over twice the amount of data that way compared to just using mkvmerge.

[setarip_old]

I can only suggest that you try it ;>}

[sneaker_ger]

I made a test on an 8 GB file and tsMuxer was almost 10% faster than mkvmerge. I couldn't test makemkv but I doubt it is more than 90% faster than mkvmerge.
Could be just my system, though..

[Ghitulescu]

Learning doesn't hurt, but you can skip frames in Matroska no matter the format because of the timecodes.

This works only during playing on a PC. Apparently the OP wants to convert back to film a telecined PAL material. So the answer is no, not without recoding, and yes, process the audio and leave the video alone, unless you know what you're doing.

[kartikoli]

thanks for clearing my doubts friends ,,, And my other point still holds; he said the length would decrease, but that's not true. u guys were correct in assuming my intentions [dropping frames does not decrease length]

Well, at least his threads are in the correct section ... :roll:

This is really getting confusing. He should explain better and actually follow the advices given to him... i may be noob in video/audio editing but as forum knowledge goes i have moderated many of them and know its functioning :roll:

i did try those advices before opening this thread

@kartikoli

(I guess it's okay for me to respond since two moderators have posted to this thread)



Try loading the file into "tsMuxerGUI", highlight the videostream and change the fps to the equivalent of 23.976fps (24000/1001).

Save as "BluRay" (Should take about 5 minutes)

Load BluRay "package" into MakeMKV and save as MKV...
thanks for the help will try it

problem solved by increasing the length of the audio and successfully created 1 test movie 'the mask of zorro'

[sneaker_ger]

This works only during playing on a PC.

Can't argue with that 'cause I don't have any "hardware" player capable of playing Matroska. But which players did you test? Just curious, since Matroska is designed to allow VFR those players could be considered broken.

[Ghitulescu]

The players for PC are much more versatile than anything equivalent "on hardware", not least because of frequent updates, in case something goes wrong (I think 8 is the maximum FW revisions I had ever seen for a specific HW, media for my gear is about 1.5, but this will increase again due to BD FWs, which are legally required to be published).

If a BD player and/or a mediatank/mediaplayer (HDD with video-out) cannot often support simple implementations of MKV, why would support VFR, which on the HW side requires a delicate and thus error-prone timing - a PC player simply lets the HW driver do the display timing (it's not that simple but quite)?

Moreover, concerning the faulty implementation, I haven't yet seen a HW player that correctly lists its capabilities, instead there's a mixture of formats, codecs and containers - Thank you for buying the most advanced media player. Supported formats: DVD, AVI, DivX, xVid, MPEG-4, MKV, H.264, OGG, AC-3, FLAC in resolutions up to 1080p.... Sounds familiar?

No, it's not faulty, is just a subset of a format, which BTW is not standardised.

[AnonCrow]

On the original question:
If one doesn't mind/notice the jerkiness caused by just removing frames,
is there a tool that would allow removing (as in saving some space too, not just setting timecodes to 0)
b-frames (not B-frames) from a H.264 stream while doing a direct stream copy on the other frames ?
Regardless of whether or not one wants to change the timecodes on the frames adjacent to the removed b-frames, to keep duration the same or not.

And the same for P-frames (only a few of them per GOP obviously) ? The tool would of course have to double-check that no MBs use any parts of the removed P-frame as reference and/or re-encode only the needed MBs to use a different reference frame.

[sneaker_ger]

The players for PC are much more versatile than anything equivalent "on hardware", not least because of frequent updates, in case something goes wrong (I think 8 is the maximum FW revisions I had ever seen for a specific HW, media for my gear is about 1.5, but this will increase again due to BD FWs, which are legally required to be published).

If a BD player and/or a mediatank/mediaplayer (HDD with video-out) cannot often support simple implementations of MKV, why would support VFR, which on the HW side requires a delicate and thus error-prone timing - a PC player simply lets the HW driver do the display timing (it's not that simple but quite)?

Moreover, concerning the faulty implementation, I haven't yet seen a HW player that correctly lists its capabilities, instead there's a mixture of formats, codecs and containers - Thank you for buying the most advanced media player. Supported formats: DVD, AVI, DivX, xVid, MPEG-4, MKV, H.264, OGG, AC-3, FLAC in resolutions up to 1080p.... Sounds familiar?

No, it's not faulty, is just a subset of a format, which BTW is not standardised.

To sum your post up: you didn't actually test any player - correct?

Matroska doesn't have any "real" CFR mode (only a standard duration flag), every frame gets a timecode, even for CFR streams. Delays are also implemented solely by the timecodes. I'm not saying that your speculations are wrong - but without any tests they are only that: speculations.

[setarip_old]

@kartikoli problem solved by increasing the length of the audio and successfully created 1 test movie 'the mask of zorro' And what software did you use to accomplish this, tsMuxeRGUI plus MakeMKV, or something else?

[Ghitulescu]

To sum your post up: you didn't actually test any player - correct?

Matroska doesn't have any "real" CFR mode (only a standard duration flag), every frame gets a timecode, even for CFR streams. Delays are also implemented solely by the timecodes. I'm not saying that your speculations are wrong - but without any tests they are only that: speculations.

LG, but with CBR. I don't use anything that is not standard.

[kartikoli]

@kartikoli And what software did you use to accomplish this, tsMuxeRGUI plus MakeMKV, or something else?

Goldwave and audecity .... it wasnt that easy had to do some manual scnc work but it did the job perfectly