Additional Frame Rates

[jt49]

In version 10, I would like to see video export with additional frame rates like 30.00 and 60.00 (in addition to 29.97 and 59.94, presently called 30 and 60).

[Picsel]

Something I still do not understand with video frame rates.

There are two different standards for TV movies which were inherit from the old good times of CRT.

USA based on 60fps and European one  based on 50fps

 The power supply were generated with alternative currents  60 Hz in USA countries  versus 50 Hz in European countries  and the TV signal was based on two  interlaced frames 30 Hz and 25 Hz just in order to minimize the stroboscopic and glitering effects with the light at home ( 29.97Hz and 59.94Hz have been created by american Tv industries for technical purposes )

Obviously there is no more interest today with the progressive scanning, but the standard  remained the same in order to ease the market transition between the both technologies.

So I would like to understand the reason for your demand since european TV standards are based on  720p 50fps (HD)  and 1080p 25fps (Full HD) since years and now for 4K or 8K   ( all the digital Tv movies are based on this format - and so digital cameras sold in Europe) and 24fps for movies industry  ?

Best regards

Daniel

 

[jt49]

Hi Daniel,

I am not that much interested in TV standards. I normally to run my AV productions, and those of my club members using a PC (or notebook), either on my PC monitor or using a projector. In both cases the refresh rates are around 60. So frame rates like 25 or 50 are not so good. So in my case, 60 seems the way to go. But what does 60 mean? My PC monitor runs at rates about 59.9503, my notebook with its own monitor at a rates slightly greater than 60.0. Looking at the specification of our projector, I see various refresh rates, depending on the resolution (59.95 for WUXGA,  60.0 for FullHD). Having this in mind it might be an advantage to have a choice between 59.94 and 60.0 when exporting videos from PTE.

As I said in some other post: I often receive videos from others that run at 30.0. If I cut such a video in PTE, it would fine if I could render it at the original frame rate (30.0, and not 29.97).

Best regards,
jt

[Picsel]

Hi jt

The refresh rate is a parameter which is independent of the video coding process frame rate. I would guess that it could be a problem with interlaced video but should not be with progressive ones. However I agree it could be better to use a video projector with a refresh rate = N x the video fps.

It could be interesting to get the point of view of an expert in video projection technics on that.

For your problem of mixing video clips having different frame rates, personnaly I would convert all of them at the same fps before mixing them together inside the same AV show whatever their original frame rate.

Best regards

Daniel

 

[jt49]

Hi Daniel

Of course, the video's frame rate and the monitor's refresh rate are independent.But as you say, on a monitor with a refresh rate of (say) 60 Hz it is recommended to run videos at 60 or 30 fps (and not 50 or 25). So it would be fine if PTE would offer more possibilities to match the parameters of particular environments.

I have not been thinking of mixing clips different frame rates. Think of simple jobs like making a few video cuts or of re-encoding, just for a single video clip. Typically, in a video editor or even in a re-encoding tool like XMedia Recode you will find the output option "Use original frame rate". For this kind of jobs PTE is not prepared. On the other hand, the underlying encoder (used by PTE) would be able to do it.

I don't think that offering additional frame rates (like 10;12.5;15, 23.976; 30.00; 60.00)  will be a big affair. The only drawback that I see is that some people who do not know much about video might become a bit more confused than they are already today.

Best regards,
jt

[Igor]

In my country we have 25p/50p TV standard, as in Europe. However I always record my videos at 60p or 30p. Never in 25p/50p. Explanation is very simple: all modern TVs can play video content with any frame rate (regardless a country). However computer monitors and laptop screens almost all use 60 Hz frame rate. And these computer screens very rarely allows to set 50 Hz mode (or it looks too complicated to switch refresh rate just play some video file). So the best option to play home video would be 60p video. 60p video on 60Hz monitor looks fine. If I play 25p/50p videos on 60Hz screen - video is not smooth.

[Picsel]

Igor I can agree with you only on one point. As I said in my previous post it is better to have a display system (screen or videoprojector) which uses a refresh rate = n times the video frame rate.

But you must consider that most of the cameras sold in european countries works at 25/50  even 100fps (*). I have no problem to read them on my laptop screen whose refresh rate is 60Hz (you should notice that under W10 and with different systems it is possible to choose the refresh rate)

(*) Some of them at 24fps for movie theater shows.

All the digital video Tv which are broadcasted by european companies are for most of them at 25fps for full HD. Manufacturers of TV sets offer different frame rates. My LG Tv set works at 200Hz.

Best regards

Daniel

[Igor]

Daniel,

Yes, it's a problem with these cameras. For this reason, I purchased Sony camera from another region to have possibility record video at 30p/60p.

My recent Canon camera allows to record video at 25p, 30p, 50p and 60. 

iPhone always to choose between 30p and 60p regardless a country.