Video upscaling question

[lutinor]

Hi all,

Sometime i need to upscale sd video to hd format but i need to focus on 23fps (cause bd restriction).

Question : If the original bitrate is 1000, is it usefull to put more than 1000 in the 720p target video ?

Thx in adv,

Max.

[Groucho2004]

Some info about the source video (type and resolution) would be helpful.
Also, what does "need to focus on 23fps" mean?

Generally, you'll have to increase the bitrate when upscaling.

[lutinor]

Some info about the source video (type and resolution) would be helpful.
Also, what does "need to focus on 23fps" mean?

Generally, you'll have to increase the bitrate when upscaling.

It's a 720x576 23fps original video.

In blueray, there isn't 72x576 in 23fps. I must use 1280x720 cause its the nearest resolution with this kind of frame rate.

[poisondeathray]

Do you mean 23.0 FPS or 23.976 FPS? 23.0 FPS isn't compliant at 720p either

If it's 23.976, Why don't you resize it to 720x480 and use --pulldown 32 --fake-interlaced ?

[lutinor]

Do you mean 23.0 FPS or 23.976 FPS? 23.0 FPS isn't compliant at 720p either

If it's 23.976, Why don't you resize it to 720x480 and use --pulldown 32 --fake-interlaced ?
23.976 fps but tbh i haven't though about 720x480, will it work on pal hardware?

EDIT: i don't see in bd standard 720x480 23.976 :(

[poisondeathray]

23.976 fps but tbh i haven't though about 720x480, will it work on pal hardware?


I don't know... I'm in NTSC land

another option that would work for sure would be to speed up audio, then use 720x576 25fps with --fake-interlaced



EDIT: i don't see in bd standard 720x480 23.976


That is what the pulldown is for
http://sites.google.com/site/x264bluray/home/480p-ntsc

[amtm]

BD doesn't allow 23.976 for any resolution. It does allow 24fps for various resolutions though.

[sneaker_ger]

I wouldn't go the pulldown route, that way you will probably disable the 24Hz mode many modern devices support. 1280x720p23.976 is the way to go. And yes, please use more than just 1000 kbps.

BD doesn't allow 23.976 for any resolution.

Wrong. (http://forum.doom9.org/showthread.php?t=154533)

[poisondeathray]

BD doesn't allow 23.976 for any resolution. It does allow 24fps for various resolutions though.


By "23.976", most people really mean 24000/1001 , it's just used as an approximation. It is alowed in BD spec

[amtm]

My bad. I had only quickly glanced art the specs and missed that.

[lutinor]

I wouldn't go the pulldown route, that way you will probably disable the 24Hz mode many modern devices support. 1280x720p23.976 is the way to go. And yes, please use more than just 1000 kbps.



Wrong. (http://forum.doom9.org/showthread.php?t=154533)
Something like dual bitrate or 150% ? Any idea ?

[hello_hello]

720x576 is a resolution supported by Bluray, although I also don't know whether you mean 23.976fps.
http://sites.google.com/site/x264bluray/home/576p-pal

Edit: Looks like I was a bit slow, someone else has already posted the link.

[lutinor]

720x576 is a resolution supported by Bluray, although I also don't know whether you mean 23.976fps.
http://sites.google.com/site/x264bluray/home/576p-pal

Read my original post again plz :)
My original video isn't standart at all. It's a 720x576 movie in 23.976fps and i must tranform to a bd standart, that's the prob

[sneaker_ger]

Something like dual bitrate or 150% ? Any idea ?

Since you're encoding for Blu-Ray, just use as much bitrate as fits on your optical media.

[mp3dom]

You can:
- Resize your 720x576@23.976p to 720x480@23.976+pulldown to 29.97
- Keep the file at 720x576 and speedup (video and audio) at 25p+fake interlaced (you can do audio pitch correction for the speedup)
- Keep the file at 720x576 and apply a hard 2^12:3 pulldown (2 judder every seconds), encode as pure interlaced. <- This can hurt PAL people, because on PAL land movies gets always accelerated. They're not accustomed to judder.

Actually, the PAL lands have the highest compatibility. On the BD side, PAL territories are obliged to support ALL the resolutions and framerates (720x480@60i/720x576@50i/1280x720@24/50p/60p and 1080@24/50i/60i) while NTSC territories are not forced to support 50Hz output.

[hello_hello]

Read my original post again plz :)
My original video isn't standart at all. It's a 720x576 movie in 23.976fps and i must tranform to a bd standart, that's the prob

Well originally you said 23fps so I figured you mightn't have described the video err.... accurately.

[lutinor]

You can:
- Resize your 720x576@23.976p to 720x480@23.976+pulldown to 29.97
- Keep the file at 720x576 and speedup (video and audio) at 25p+fake interlaced (you can do audio pitch correction for the speedup)

My question will sound stupid but if you speedup, the result will be 'not good to see' am i wrong ?

[mp3dom]

If you speedup you still have 1:1 mapping (1 film frame = 1 pal video frame) with no interpolation/ghosting/blending/artefacts/judders. You just take 25 frames to create a second rather than 24. The only downside is that the movie length will be 4% shorter (or playback will be 4% faster) and the same apply to sound pitch (but this can be fixed with a time-stretch)

Judders appears if you use pulldown (because pulldown is frame-repetition with some cadence)

[lutinor]

If you speedup you still have 1:1 mapping (1 film frame = 1 pal video frame) with no interpolation/ghosting/blending/artefacts/judders. You just take 25 frames to create a second rather than 24. The only downside is that the movie length will be 4% shorter (or playback will be 4% faster) and the same apply to sound pitch (but this can be fixed with a time-stretch)

Judders appears if you use pulldown (because pulldown is frame-repetition with some cadence)
Basically :

23.x fps, 24 fps -> 25 = no visible change (if you forget the shorter total time)

?

one thing : If you speed up the sound, will you hear it ? Or the voice the stay 'natural' ?

[AnonCrow]

one thing : If you speed up the sound, will you hear it ? Or the voice the stay 'natural' ?
If you don't apply timestretch and compare the original and sped-up version, you'll notice the difference in a blind test.
If you listen to only one, you might not be able to tell which one it is - trained ears will, but get used to it.

If you do apply (high-quality) timestretch, it's unlikely that you'll notice that people simply speak 4% faster.
Decent quality real-time timestretch (eg. Scaletempo , used by a lot of FOSS players, or timestretch built-in to WMP) is good enough at such small speedchanges. It's only once you go beyond 0.5x - 2x that the artifacts created by the timestretch will become annoying ( but bearable)

[lutinor]

Last question :

Which tool is the best to 23.x/24 -> 25 ?

[gyth]

Avisynth (http://avisynth.org/mediawiki/AssumeFPS)

AVISource("FILM_clip.avi") # Get 24fps clip
LanczosResize(768, 576) # Resize to PAL square-pixel frame size.
AssumeFPS(25, 1, true) # Convert frame rate to PAL, also adjust audio.
SSRC(44100) # Restore audio sample rate to a standard rate.

[Ghitulescu]

SSRC(44100) # Restore audio sample rate to a standard rate.
With the notable exception of VCD no other "standard" in video had 44.1kHz as sampling rate. :p

[lutinor]

Avisynth (http://avisynth.org/mediawiki/AssumeFPS)

AVISource("FILM_clip.avi") # Get 24fps clip
LanczosResize(768, 576) # Resize to PAL square-pixel frame size.
AssumeFPS(25, 1, true) # Convert frame rate to PAL, also adjust audio.
SSRC(44100) # Restore audio sample rate to a standard rate.

Wait, i use x264.exe cli with avs input but how i will get audio file with x264 ?

[Blue_MiSfit]

You won't :) You can use something like the SoundOut() plugin to output a WAV (or AC3 or MP3 or whatever you want), or many other tools like VirtualDub.