FORUMS: list search recent posts

Compression advice

COW Forums : Compression Techniques

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Ben Hull
Compression advice
on Jul 28, 2017 at 7:46:50 am

Hello everyone.

Long time reader, first time poster, so forgive me if this has been answered many times in the past and I’ve just not found it.

I am making a series of 50, 35 minute videos for a client, who wants to make them available to watch on an app. I suspect that they will stream the videos, but have also talked about wanting to make them downloadable too.

I shot 1920 x 1080 25fps on multiple (different) cameras, converted the lot to Pro Res 422in order to edit smoothly in FCPX, leaving me with an edited Pro Res 422 Master file of roughly 35 gigs.

Using the excellent YouTube Compressor Droplet which I found on Creative Cow (thank you!) 35 gigs becomes 3.5 gigs, but it’s still far too big.

I rescaled to 1280 x 720 which made a huge difference but again, still too big.

I then tried using the Handbrake 1280 x 720 preset, and got it much smaller (almost a tenth smaller it would seem), but the graphics looked slightly pixellated, actually, stripy, when you went fullscreen with the compressed video.

Pushing the quality up on this preset may be one option, but I’m pulling what little hair I have out, lost in a world of framerates and bitrates and really need some help.

I’m pretty certain that many of you brilliant people may have encountered such problems in the past, and I’d be really grateful for any advice or step by step pointers that you could give me.

Many thanks,

Ben


Return to posts index

Craig Seeman
Re: Compression advice
on Jul 28, 2017 at 3:18:12 pm

[Ben Hull] "35 gigs becomes 3.5 gigs, but it’s still far too big."

Too big for what?
If it's subjective it's hard to give an objective answer.

That math for file size is basic middle school/high school math.

File size equals duration times bitrate.
Lower the bit rate lowers the file size.

Quality is another issue and that's subjective.
As you lower the bitrate generally you'll lower the quality.
Lowering the frame size can counteract that.
Basically it's bits per pixel (frame size and frame rate are two important factors).

So what's acceptable to your client is subjective. Without a specific use it's hard to offer much in the way of detail.
YouTube and Vimeo have recommendations if that's where they're headed.



Return to posts index

Ben Hull
Re: Compression advice
on Jul 28, 2017 at 4:50:47 pm

Craig, thank you very much indeed for your reply, I really appreciate it.

Thank you too for spotting the vital flaw in my email- stress will do this to a man!

The videos are for a 'start up' app, and the client is concerned about the amount of server space 50, 3.5 gig videos will use, as well as stream and download costs- hence wanting them as small as possible to try and keep the costs down.

I already compress my videos for YouTube and Vimeo, but thank you for the pointers, as well as the really useful maths, and I shall further investigate.

All the best,

Ben


Return to posts index


Craig Seeman
Re: Compression advice
on Jul 28, 2017 at 8:20:00 pm
Last Edited By Craig Seeman on Jul 28, 2017 at 8:23:34 pm

[Ben Hull] "amount of server space 50, 3.5 gig videos will use, as well as stream and download costs- hence wanting them as small as possible to try and keep the costs down."

Ah, space and bandwidth considerations. If you can get away keeping things limited to 720 that could help. You may need to present a couple of different bitrates (and therefore sizes) and see what's acceptable to him since he has to consider quality vs size vs cost in his case.

I haven't had to do that in a while but when I did my workflow usually involved downloading a Vimeo and YouTube video at 720 and examining the specs. Then I'd use those specs to encode to show the client. Basically, these days, the typical viewer expects "YouTube" quality so that's what I'd use as a guide.

I just downloaded a Netflix trailer from YouTube at 720 and I see.
H.264
Video Bitrate 1100kbps
Audio Bitrate 128kbps
Profile Main
Level 3.1

at 35 minutes that would be about 323MB but you may want to test at higher and lower bit rates so client can see impact on quality.


Return to posts index

Ben Hull
Re: Compression advice
on Jul 29, 2017 at 7:44:24 am

Craig, that is fantastic, thank you!
It's exactly the help I needed, and very much appreciated.
All the very best,
Ben


Return to posts index

Craig Seeman
Re: Compression advice
on Jul 29, 2017 at 8:09:28 pm

You're welcome of course.



Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]