Two general editing questions regarding file types.

CubeAce wrote on 3/24/2019, 6:40 AM

First.

Does it matter if the computer monitor refresh rate is different from the target projects framerate for the smoothness of playback you see on a monitor either while editing or on playback of the finished file?

Second.

Whenever I use the HEVC codec for conversion, I never get a picture within the icon for the file similar to using other codecs when viewing a folder and on uploading to a hosting platfrom the video always presents as a black rectangle and never with a chosen frame.

Are those your experiences? Is it a windows 7 thing?

Can it be rectified in any way?

Thank you for any feedback.

Ray.

Comments

johnebaker wrote on 3/24/2019, 9:10 AM

@CubeAce

Hi Ray

. . . . Does it matter if the computer monitor refresh rate is different from the target projects framerate for the smoothness of playback you see on a monitor . . . .

No - the refresh rate of the screen is usually 60 fps or more.

. . . . HEVC codec for conversion, I never get a picture within the icon for the file . . . .

AFAIK it is Windows 7's Explorer not supporting extraction of HEVC thumbnails.

HTH

John EB

CubeAce wrote on 3/24/2019, 10:29 AM

Thanks John.

So there is no separate codec thumbnail generator that can be installed similar to the one I have from Nikon allowing me to view their NEF raw format files? Pity. I assume this is just one more way Microsoft are getting people to migrate to Win10.

The first question arose due to another forum where best practice in video editing was being discussed. Where one member said they stuck to refresh rates close to the frame rate of the project which made me wonder as I assumed faster monitor refresh rates were just less tiring on the eyes and had little to do with any possible strobing or stuttering effects although some TV manufacturers suggest a better flow of action with higher refresh rates. I would have thought that and what type of screen you had where some are LED with a backlight and others use OLED and the speed at which they work had more influence.

Ray.

johnebaker wrote on 3/24/2019, 11:08 AM

@CubeAce

Hi Ray

. . . . stuck to refresh rates close to the frame rate of the project . . . .

That could mean running the monitor at a framerate of 25 or 30 fps which would be running below optimum refresh rate. This low fps would causes more issues with progressive video and for some people who are sensitive to these low refresh rates tiring viewing and may be worse if sensitive to flicker.

When working on my laptop with 4K video I have proxy files enabled and the Reduce resolution and Reduce framerate options of preview monitor options turned on to ensure smooth playback and there have no issues with flicker despite the reduced framerate.

. . . . some TV manufacturers suggest a better flow of action with higher refresh rates . . . .

I suspect this is to give smoother playback of Progressive video - this has been covered in at least one topic in the forum already. Interleaved video is much smoother for the same framerate.

. . . . LED with a backlight and others use OLED and the speed at which they work had more influence . . . .

The main 'influence' between the 2 technologies is the contrast ratio (CR) and brightness.

OLED's have pixels which produce their own light, ie are true ' organic LEDs', and have a much higher CR and increased brightness than the backlit screens (LCD) screens where the light must pass through the RGB pixel filters, thus losing brightness because you are subtracting from the backlight intensity and losing contrast because the LCD screens can never block all the transmitted light.

HTH

John EB

Scenestealer wrote on 3/25/2019, 3:56 PM

@johnebaker

Hi John

When working on my laptop with 4K video I have proxy files enabled and the Reduce resolution and Reduce framerate options of preview monitor options turned on to ensure smooth playback and there have no issues with flicker despite the reduced framerate.

I presume you are talking about 4K @25fps? Do you think the preview is designed to reduce to lower than 25fps using this option as I have not seen any evidence that this is happening even with the full res XAVCS 4k files on the timeline, nor do I see any increase in smoothness or CPU load with this option on or off? With 50P HD files it does have an effect and that is what I would expect, but I doubt this option would try to force the fps below 25.

Peter

johnebaker wrote on 3/26/2019, 3:18 AM

@Scenestealer

Hi Peter

. . . . I presume you are talking about 4K @25fps? Do you think the preview is designed to reduce to lower than 25fps using this option as I have not seen any evidence that this is happening . . . .

You are correct about the 4K 25fps video.

I read somewhere that the preview framerate is dropped down to 15 fps - maybe that was a typo - with the Reduce framerate option selected, however I cannot find it again.

Certainly on some pans the jerkiness is more apparent than when played at 25fps - this was also more noticeable with my Sony XR520EV and AS30V cameras, as these 2 cameras were Full HD 1920 x 1080 I normally did not reduce the framerate for preview.

John EB