bad quality video converted to mp4 quicktime from mpeg 2

[god_mattus]

I am currently working on a project that is going on a plasma tv network around a venue in england.

I am creating my files in after effects and adobe premiere and exporting them as mpeg2 pal and then converting them into mp4's.

my mpeg settings are:

*highest quality
* 25 fps
* Frame width 720
height 576
*bitrate encoding vbr, 1 Pass
*minimum bitrate 2.4990
*target bitrate 3.8242
*maximum Bitrate 4.0000

I have variable multiplexing and no audio.

i then convert them in videora converter to mp4s with the following settings:

mpeg4/320x240/1500kbps Stereo/128kbps

I think this is what the person before me did but this doesnt look right.

I would do them as mpeg2's but i think the scheduling machine only plays mp4's??


can anyone help me?

cheers matt

[Baldrick]

320x240 wont look good on TVs.

Scheduling machine? more info about the player would help.

[god_mattus]

I will try and get some more info on the machine.

would it help if i just encoded it as a quicktime movie straight from premiere.

also what dimensions would you suggest for a tv?

thanks matt

[Baldrick]

Well, it might look good on a 10" TV but anything bigger I would at least use 640x480 but it depends what the player supports also.

And it would be best to convert directly to a format that the player support instead of converting to lossy mpeg2 video. Or convert to a less compressed format like DV-AVI using after effects and then convert it to mp4.

[god_mattus]

ok

could anyone hazard a guess of what the resolution should be if it was a 32" screen?

I know its very vague but please can anyone help i need to encode it in an hour to quicktime!

would 640x480 still be ok for a 32"?

cheers

matt

[guns1inger]

Nope. 32" screen is probably at least 848 x 480 (cheap, low res NTSC widescreen), and probably higher at 1366 x 768 ish or better.

Your process is very much geared to producing very low quality video at the moment. The initial encode's bitrates are way too low for the resolution, and then you encode it again to an even lower resolution. Neither mpeg2 nor mpeg4 like to be re-encoded. They are end viewing formats, and repeated encoding kills the quality very quickly.

Start back at the beginning.

What exactly are the displays ?
What exactly are the players ?
What are the limitations you have to work to ?
What are the quality expectations ?

You have to answer these questions before you start encoding the video.

[god_mattus]

ok

my limitations are that i think it has to be an mp4 so everything done previously was done to an mp4 quicktime file.

the displays are just a series of animations done in after effects and and also video footage combined in adobe premiere pro 1.5

the quality expectaion is quite high but i need to keep the 12 minute piece to a file size lower than 2gb.

The player is simply a flash drive that i insert the memory card with the files on into and it automatically plays the files.

I am no longer going to encode it to mpeg2 I will do it straight to quicktime from premiere.

would this be ok?

and if so can you recomend settings?

It will be pal

please help guns1nger!

cheers matt

[god_mattus]

can anyone help at all?

[god_mattus]

u there guns1nger!?

[guns1inger]

You only answered half the questions, however 12 minutes in 2 GB allows you huge bitrates, so high resolutions are viable, if your playback equipment supports them. This is really the missing piece of the puzzle - what does your playback equipment limit you too ?

[god_mattus]

it limits me to using mp4's

in any other case I would just encode it to mpeg2 but I'm afraid i am limited to mp4s which is a bit of an alien format to me.

as far as i know its just a very simple machine that i plug the flash card into and it plays it on a loop.

has that answered your question?

thanks once again for all your help!

please get back to me when you have this.

[god_mattus]

i meant when you get this!

and also when you have time!

[guns1inger]

You can use a bitrate up to around 22000kbps, which is very high. Probably higher than can be read continuously from the card. Ignore the compression method for the moment. What you need to find out - not guess at, but find out - is what the maximum resolution and bitrate that this device can comfortably playback at. Then encode your video just short of this. There is not point encoding at 3500 kbps @ 640 x 480 if it will play back at 15000 kbps @ 1366 x 768. There is no comparison in image quality between the two.

But until you know what you are meant to be doing, you are just guessing. Go under, and it looks like crap. Go over, and it may not play at all.

[god_mattus]

ok

I shall find out the maximum res and bitrate.

and then come back to you.

this is very much appreciated

cheers

matt

[oldandinthe way]

There are two trends in video. HD - improvement on DVD and Apple - low resolution. Quicktime is typical Steve Jobs - keep the screen small to mask the inferior quality - this goes back to the original Mac. Since most of his customers are non-technical they don't know that better exists.

[god_mattus]

ok I have just found the manual.

It tells me that the max resolution it will play is 720x480

however it mentions nothing of bitrates.

what would be a safe bitrate but good quality to encode it as?

Keeping in mind it has to be less than 2gb.


matt