Serato Video General Discussion

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 Serato Video General Discussion
MPEG Standards Explained
Talk about Serato Video and Video-SL.

MPEG Standards Explained

QECRUSH 10:12 AM - 15 December, 2007
Hey there fellow DJ's VJ's and everything in between. I just recently posted in another forum about a small crisis that freaked me out because the public preview of this shows that it will only support MPEG-4 which if you read what I am about to post it's simply the same high quality yet at a smaller file size which is also a good thing. One thing you will probably find yourself doing the same as I just did is realizing that unless you're using a 750GB or higher external hard drive you're pretty much going to be screwed in the long run. I went with the Terabyte Drive by Western Digital because it was a small price to pay for the extra space.

I subscribed to a MPEG-2 Format DVD Subscription, I purchased a TON of DVD MUSIC VIDEOS recently and for the last week have been ripping them getting ready for this release and a huge GIG I have coming up on New Years Eve; like the biggest event I would say sale wise in my 11 year career so needless to say I am trying to deliver diamonds on a sterling silver expectation so that this client has no chance to consider anything for the next 5 years. Finally.... the war against BANDS is over... DJ's WIN!!!! (haha just kidding) Anyway as for the DVD ripping let me tell you at 3.5 hours per RIPPED DVD the process being as it takes so long I really wasn't too thrilled to read that VIDEO-SL wasn't going to support MPEG-2 because that was a huge backtrack. (And we thought building over views with 1.4 was a tedious task) While it doesn't show on the marketing for this it will support MPEG-2 I did some research to find out what are the differences between MPEG-2 and MPEG-4 and from what I can gather (read below) it's really just a smaller file size. MPEG-2 apparently is what they use in Movie Theatres and put on DVD's that you buy in the store. I know for me personally I am really trying to niche the market for this in my area and "re-introduce" DVD parties the way it should be done. This entire idea of what the Serato Team has done here is just the "Filet Mingon" of the Video/DJ Industry and I think we're all in for the best future ever! Here is the research explanation I found on www.jakeludington.com

"MPEG Standards Explained
You frequently talk about video formats, can you explain the difference between MPEG-1, MPEG-2, and MPEG-4 and what their possible uses are?

There are so many different formats floating around, I frequently find myself double-checking to make sure I'm referencing the right thing. Without realizing it, many of us spend a great deal of time watching MPEG-2 format video either on DVD or delivered over cable and satellite to digital subscribers around the world because it remains the accepted compression standard for the television industry. Assuming you have the right software installed on your system, most of the subtle differences between the various video formats should be transparent. Things get tricky when you're missing a codec, which is software designed to interpret the audio or video information contained in a file.

MPEG stands for Motion Picture Experts Group, the standards body made up of many large companies involved in technology and content creation in the video industry.

MPEG-1 compression is the oldest MPEG compression standard. At its highest quality level, MPEG-1 formatted video is compressed to approximately 1.5Mbps. MPEG-1 video compression finds commonalities between frames in a movie to generate subsequent frames, reducing the amount of video information required to store an entire movie. For instance, if several frames in a row all contain the same still image of a living room, the compression tells the file to keep displaying the same image for each of those frames until it hits a frame where the image changes, eliminating the actual duplicate frames from the file to reduce the overall size (I'm oversimplifying a little bit, but that's the basic idea). MPEG-1 compression is made up of several layers of information, with MPEG-1 Layer 3 (or MP3) representing the audio portion of the file compresion. MP3 reduces the file size of audio data by eliminating high and low frequency sounds undetectable by human hearing, reducing the overall size the audio portion of a video file. MPEG-1 video is used for VCD video disks and is typically no better than VHS quality video.

MPEG-2 improves upon the MPEG-1 standard by increasing the data throughput a video file is capable of. Where MPEG-1 maxes out around 1.5Mbps, MPEG-2 is typically compressed to between 3.5Mbps and 6Mbps. MPEG-2 is the standard used by DVD and SVCD formats for encoding video, as well as the digital cable and satellite industries. Like MPEG-1, MPEG-2 is a lossy compression standard, meaning some of the originating video source is removed to make the file smaller. Because MPEG-2 video removes some of the video information from the file, it's occasionally possible to see blocky artifacts in the video file, especially in high motion scenes. This is less true for MPEG-2 video compressed in the 6Mbps range, because the quality level approaches a range where defects are imperceptible to the human eye, but as the quality level is improved the file size gets larger.

MPEG-4 treats compression differently than either MPEG-1 or MPEG-2. Because of this compression difference, MPEG-4 video output offers higher image quality at much smaller file sizes than either MPEG-1 or MPEG-2 are capable of. MPEG-4 compresses files in a range from 5Kbps to 10Mbps making it adaptable for delivering video to everything from cell phones to HD quality output. Instead of interpreting each individual frame of a video, MPEG-4 compresses images by dealing with objects in the video, meaning it efficiently reuses image information without throwing away as much image data. Two of the more commonly available uses for MPEG-4 are DivX movies, widely found on p2p networks and the audio and video data being created through Apple's QuickTime format as MP4 video and AAC audio."
Deejay Z 12:34 PM - 15 December, 2007
Thanks Good Read....
Killbill 12:45 PM - 15 December, 2007
Yeah, nice job man, thanks.
Kenny Q 5:12 PM - 15 December, 2007
I subscribed to a MPEG-2 Format DVD Subscription too and I'm not looking forward to converting my files.

I don't know much about video and MPEG standards but here are some of my questions:

Are MPEG-4 the same quality as MPEG-2?

Will it look just as good on a huge screen?

Can I use DivX files?

Will the DivXfiles look just as good as the MPEG-2 files?

Thanks,
Kenny Q
nobspangle 6:02 PM - 15 December, 2007
DivX is a type of mpeg-4. mpeg-4 is generally better quality than mpeg-2 with small file sizes. If you want the best quality use h.264
Deejay Z 6:04 PM - 15 December, 2007
h.264 uses more processor speed right?
nobspangle 6:17 PM - 15 December, 2007
right, there's always a down side.
Deejay Z 6:20 PM - 15 December, 2007
so I guess mp4 is the lesser of two evils :-/
nobspangle 6:25 PM - 15 December, 2007
mp4 is just a container. An mp4 file could contain h.264 video. If you're talking about the codec you need to say mpeg-4
Deejay Z 6:29 PM - 15 December, 2007
shit I getta use to this haha!
marx 7:34 PM - 15 December, 2007
mp4 is a GREAT format.

For newbies:

Think of a mpeg as a wave files

Think of a mp4 as a mp3 file

yes there "are" differences but its slight....but the size difference is pretty big. it all depends on how you convert the video...just like mp3's theres differences in not only bitrate but in resolution with video.

Personally this is how I am now converting all my videos now:

audio = 512 aac (5 mb difference between 320 & 512 is nothing in the video world)

video = 3000 kbps
640 x 480 resolution
29.97 progressive framerate

I use tmpgenc to convert. I like the batch proces...load it up let it run while you sleep.
Kenny Q 7:51 PM - 15 December, 2007
Quote:
mp4 is a GREAT format.
I use tmpgenc to convert. I like the batch proces...load it up let it run while you sleep.


I need to start converting soon.
I have a lot of mpeg-2 videos.

What about tagging?
Is there a tag&rename program out there for video?
marx 8:08 PM - 15 December, 2007
not that i know of. but tagging the mp4 in serato does work
Deejay Z 8:12 PM - 15 December, 2007
For Quicktime Pro....Can someone tell me the settings??



Marx I did ur convert using Quicktime and it came out to 100mb for Bojangles??? Is that right?
marx 8:21 PM - 15 December, 2007
yep thats about right. its that big because the bitrates @ 3000. You can lower that to make the size smaller but thats where your quality will go. I play on a 12ft screen so the quality needs to be good. But this will also insure that it will look good on plasmas.
Deejay Z 8:29 PM - 15 December, 2007
So thats like 10,000 Vidz on a TB give or take....how much difference will 2500 bitrate be....Also what is your keyframe setup at? Thanks
marx 8:55 PM - 15 December, 2007
in tmpgen i an preview the size b4 the render. The video i'm looking at is:

4000= 139 mb
3500= 122 mb
3000= 106 mb
2500= 89 mb
2000= 72 mb
1500= 55 mb

I don't have a keyframe option. what are the options. For me you would use keyframe in video editing. Not for converting.
nik39 8:59 PM - 15 December, 2007
Too few keyframes when using VIDEO-SL will put a lot of strain to your laptop whenever you needle drop or backcue for example.
Deejay Z 9:00 PM - 15 December, 2007
Either Automatic or I can Select a certain number (default 24)
nik39 9:02 PM - 15 December, 2007
24 means, you have one keyframe every 24 frames. This means (assuming your a fps of 24) that for every needle drop VSL needs to decode up to 24 frames, the more frames the more strain you put on your computer, the longer it may take until you see the video on screen.
Deejay Z 9:05 PM - 15 December, 2007
Here is a screen Shot of the settings.....what do u think

img91.imageshack.us
marx 9:22 PM - 15 December, 2007
o u mean frames per second. I would use 29.97 thats the us standard. although 24 will work too. cpu usage wise i never noticed a difference. If someone does let us know.
marx 9:24 PM - 15 December, 2007
everything else in your screenshot is right on.
Deejay Z 9:29 PM - 15 December, 2007
So match the keyframe to the frame rate....both at 24?
marx 9:32 PM - 15 December, 2007
i would. do a test & make sure that the video doesn't flicker. Whats the default setting for both inputs (framerate & key)?
Deejay Z 9:36 PM - 15 December, 2007
Framerate = 15
Key = 24 Frames
nik39 9:36 PM - 15 December, 2007
marx, he is talking about the keyframe setting, not fps setting.

You can't specify a not-whole number for the keyframe setting. That makes no sense ;)
Deejay Z 9:38 PM - 15 December, 2007
nik it let me set it to a decimal....Im so confused :-/
marx 9:43 PM - 15 December, 2007
yeah figured that after the screenshot. I'm not familiar the key setting. I did some research online...i would just leave it on automatic.
marx 9:44 PM - 15 December, 2007
if after a render it plays smooth with no flickers you know your good.
Deejay Z 9:45 PM - 15 December, 2007
kk

Soooo 29.7 and Automatic Keyframe....here we go

Mpeg-4 !and not H.264 right?
marx 9:46 PM - 15 December, 2007
you might want to try this out. It does batches & its free :"
marx 9:46 PM - 15 December, 2007
yes to h.264 :"
Deejay Z 9:50 PM - 15 December, 2007
try what out??? So convert to H.264??
marx 9:50 PM - 15 December, 2007
Quote:
you might want to try this out. It does batches & its free :"


well bump that for basic converting. This will work to rip & convert to dvd @ the same time.
nik39 9:51 PM - 15 December, 2007
Z, I would prolly rather use your own fixed setting rather than automatic.

But decimal keyframe still makes no sense to me, but I am not an expert at video.
marx 9:51 PM - 15 December, 2007
Quote:
try what out???


this was just for general knowledge...doesn't apply to u now

Quote:
So convert to H.264??


yes
Deejay Z 9:52 PM - 15 December, 2007
Should I match the Keyframe to the Framerate (rounded up to the nearest decimal)


K, converting to H.264
marx 9:53 PM - 15 December, 2007
i can't really answer that because i still don't know what that setting does. I don't have that setting on my software.

Won't hurt to try multiple settings
Deejay Z 9:54 PM - 15 December, 2007
Update:

The default Settings for H.264 is: Frame Rate: 30 and KeyFrame: 24
Deejay Z 9:58 PM - 15 December, 2007
FINAL Settings (I Hope)

img206.imageshack.us
nik39 10:00 PM - 15 December, 2007
Quote:
you might want to try this out. It does batches & its free :"


;)
marx 10:01 PM - 15 December, 2007
Quote:
FINAL Settings (I Hope)

img206.imageshack.us



nice.
Deejay Z 10:02 PM - 15 December, 2007
good deal

Thanks for your help guys....
DJ Mad Matt 10:43 PM - 15 December, 2007
Which version of tmpgenc do I need to do a very large batch job ... I have mpeg1, mpeg2, divx, A ton of different formats that I will need to convert to h.264
marx 10:46 PM - 15 December, 2007
i use 4.0 express
Deejay Z 10:51 PM - 15 December, 2007
is that PC only program?
marx 10:57 PM - 15 December, 2007
yep sorry.
marx 10:58 PM - 15 December, 2007
a-swift might know one that does a batch convert for mac
Deejay Z 11:08 PM - 15 December, 2007
sounds good
DJ Mad Matt 11:10 PM - 15 December, 2007
Ok ... thats the same one I downloaded ... im playing with Xilisoft Video Converter 3 right now ... seems to have all the settings and batches pretty nice ... just takes a Loooooooooong time to go to h.264 in 640X480
Deejay Z 11:11 PM - 15 December, 2007
yuuup
Deejay Z 11:11 PM - 15 December, 2007
Sleep on it hahaha
DJ Mad Matt 11:17 PM - 15 December, 2007
Wow ... New Virtual DJ just came out supporting mp4 ... Thats nice so now Im not totally screwed by converting everything over. Especially till were able to buy the Video Pluging .. Kinda need Fullscreen. I did hit the buy it now button but only to get taken to a screen that says january .. hahahaha
Deejay Z 11:36 PM - 15 December, 2007
ya me 2!
marx 11:39 PM - 15 December, 2007
xilisoft does take longer then others. theres another one out their thats free that d-twizzle swears by...but can't remember the name....but i don't know if it does batch encode.
QECRUSH 7:35 AM - 16 December, 2007
I am actually using EASY CD CREATOR 10 to rip the DVDs as a buddy of mine just started version 9. It's off the hook. I have custom settings though to rip in the standard recommended settings but I turned off "letter box" mode. Also I am now ripping in MPEG-4 and it rips with an "aac codec" built in now.

The best part about creator 10 is that you can also rip cd's with it and it automatically "tags" the mp3 once your done. No need to rip it and then tag it manually or use Dr. Tag or whatever you do.

So anyway I followed the advice of a friend and I purchased creator 10 and it does everything I need to do from here on out!!!

Good luck everyone!
QECRUSH

ps - hopefully that made sense, its 2:35am and I just got done 2 shows I am 12 hours logged with music and beat!!
djsteel 11:21 AM - 16 December, 2007
Qecrush That ripper on EASY CD Creator sounds cool but you might want to think a little farther in the future. I've been doing video for years now and you will come across a lot of videos that just stop in the middle of the song to do some crappy acting that we as DJs will have to cut out and make look normal so it doesn't dumb our dance floor. This being the case I always decode my Videos from DVD's to Vob. Files so i will always have them for editing in their original state, i also do Mashup Videos which makes that even more important to me. I've found that my method of ripping and converting is very quick, flexible and efficient. This of course will not work well for people who don't have at least a 500 gig drive to dedicate to just vob files, but if your gonna do something do it right.


DVD Decrypter is the fastest I've found.

I've been told as well that in the very near future that anything you can play with quick time will play on Serato Video. I've tried AVI's but they aren't working so well right now, but i'm confident they will figure it out.

Oh And so everyone stops worrying about Hard Drive Space, it really doesn't take much space if you encode the right way. I've always been able to fix all my video in under 60 gb of space. The average file size being 50 mb.

I've got every video i could ever need, and to help those that don't have a lot of space. Try this trick I use for playing out. DJ the next ten time the way you normally play, at the end of your gig before you shut off Serato make one new folder marked songs i use. Then go to your review window and copy all those song and drop them into this new folder. Do this at the end of every gig until you realize that the number of songs in the fold isn't getting bigger. I maxed out at 450 which is a lot more then most people, I work for a Radio Station, at Clubs, Mobiles, Raves, and do Video. Which all require different stuff and i only hit 450. Most people will be around 250 to 350 if you just do one of these. If you take the time to separate these files you always use from the rest you'll notice that you have a lot of files you will never ever use taking up a whole lot of space. If you simply keep the ones you always use and a few you can't bear to be separated from you'll have a lot less mess and bunch of free space.
nobspangle 1:07 PM - 16 December, 2007
Keyframes,

Think of video as a collection of pictures (frames) in sequence. To compress the video we could take each frame and compress it like a jpeg. However what you may notice about video is that for each frame, some parts of the picture are the same as the previous frame.
For these frames we can encode just the parts that have changed which makes our file smaller. We could go through the whole video doing this with each frame only recording changes from the previous frame. This is fine if all we want to do is play the video from beginning to end however if we want to play backwards or jump to a point in time we need to decode everything that comes before that point to get the complete image.
To get around this problem we introduce keyframes, a keyframe is a frame that contains the complete image. Then when we jump to a point in time we only need to find the previous keyframe and decode from there.
If you set the encoder to automatic keyframes it will most likely try to only place keyframes at scene changes. This is fine for a video that you watch and skip through using chapters as a keyframe won't be too far away.
In Video Scratch we need to be able to jump to a point in time very quickly so you are best off forcing the encoder to introduce a keyframe at least every second. So set the keyframe setting to the nearest whole number to the framerate.

Framerate,
Choose the same framerate as your source video, NTSC DVD is either 29.97 or 23.976 fps. PAL DVD is 25fps.
No point in using any other setting as you could introduce timing issues and your video may not seem as smooth.
marx 3:18 PM - 16 December, 2007
thanks for the info.makes total sense
Serato
Nathan H 1:48 AM - 17 December, 2007
Hi QECRUSH,
Nice explanation but it glosses over one really big difference between MPEG-1/2 and MPEG-4. MPEG-1/2 are multiplexed streams so the audio is mixed up with the video whereas MPEG-4 has them separated into different streams. This means the decoding process is quite different and so while it is definitely on our list, it is not a 1.0 feature...

Hope this helps explain why we don't *yet* have support.

N
djsteel 11:22 AM - 17 December, 2007
thx I didn't know that.
VJ Justin Allen 1:04 PM - 17 December, 2007
Hey everyone. I'm new to this forum and yes, it's because of the addition of video to Serato.

One thing I haven't seen in this thread is that the images that you will be ripping from existing DVD's and then compressing again, will be 3rd generation compressions. The quality will not be that good, especially when put on a larger screen or projector.

Is Serato going to push for a "Serato" version to be released via Promo Only and other companies so that the quality isn't so bad?

Also I would imagine an issue with using MPEG2 would be the GOP structures. How is Serato going to handle them?

Anyways, I look forward to seeing this product and being able to play with it some more.
Deejay Z 3:06 PM - 17 December, 2007
Quote:

Is Serato going to push for a "Serato" version to be released via Promo Only and other companies so that the quality isn't so bad?


First Off, Welcome!!! I to hope that PO will release a serato version so it would elevate having to rip the DVDs....Which is extremely time consuming....
a-swift 6:17 PM - 17 December, 2007
so many posts here to correct, i'll just stick with the most important things to point out, although a few people have already pointed them out.

MP4 is a container format for video, not an encoding method. The MP4 container can support numerous types of video encoding, H.264 is one. Divx is another, and Xvid is yet another. There's probably even encoding methods that haven't even been invented yet, that MP4 will support. Also, along the same lines, MP4 could have audio that's encoded in any compatible format. AAC seems to be the clear choice here.

Just because I like to be right, I'll point out the fact that nearly a year ago I was telling everyone that H.264 AVC/AAC video/audio in mp4 containers would be the way to go. I even wrote scripts and a database/client daemon to encode my entire library of MPEG2 to H.264 in anticipation. Looks like I was right :-)
a-swift 6:23 PM - 17 December, 2007
Quote:
One thing I haven't seen in this thread is that the images that you will be ripping from existing DVD's and then compressing again, will be 3rd generation compressions. The quality will not be that good, especially when put on a larger screen or projector.


4th generation for anyone doing edits (without rendering to uncompressed first). i've pointed this out to a few people I know who are doing edits. The least you can do is rip to uncompressed, do your edits then render to final output. That way you don't lose a generation.

Quote:

Also I would imagine an issue with using MPEG2 would be the GOP structures. How is Serato going to handle them?


i imagine that serato will use the decoded frames directly from memory (like VDJ does), so they are not concerned about I, B frames, GOP struct, etc. Each frame is fully rendered in memory and that's what you see on the screen. it's a guess but that's the only way I could envision anything even resembling decent scratch performance being usable.

Also, i'll challenge you to stand on the dance floor and tell the difference between the VOB ripped directly from DVD and my H.264 encode of the same video. I'll blind test you one against the other and you can try and tell me which is which. I challenge you.
marx 6:33 PM - 17 December, 2007
yes h.264 is that good

imagine if we could rip it from the beta tapes instead of ripping from a dvd.

swift what bitrate do u use for the video?
a-swift 6:40 PM - 17 December, 2007
Quote:
swift what bitrate do u use for the video?


i use bitrate 2500k which gives me filesizes that are dependably less that half the size of a promo only VOB. but you'll see cats here doing 1500k and still getting real good quality at sizes that approach 25% of the original.

i'm sticking with 2500k though. i've used these on the biggest of big screens and they look good. as good as you're gonna get over a composite or s-video wire at least.
nobspangle 6:54 PM - 17 December, 2007
Quote:
4th generation for anyone doing edits (without rendering to uncompressed first). i've pointed this out to a few people I know who are doing edits. The least you can do is rip to uncompressed, do your edits then render to final output. That way you don't lose a generation.

I always used to do my edits in huffyuv, it's Windows only but you get lossless compression at roughly 2:1 not much of a saving for disk space but it makes a massive difference for disk speed.
a-swift 7:06 PM - 17 December, 2007
Quote:
Quote:
4th generation for anyone doing edits (without rendering to uncompressed first). i've pointed this out to a few people I know who are doing edits. The least you can do is rip to uncompressed, do your edits then render to final output. That way you don't lose a generation.

I always used to do my edits in huffyuv, it's Windows only but you get lossless compression at roughly 2:1 not much of a saving for disk space but it makes a massive difference for disk speed.


I've done my edits in Uncompressed 10bit, 8bit, raw YUV, etc. Yes the disk space requirements are HUGE. I warn people about the 4th gen issues but I myself will likely edit in ProRes-422 which is still VERY high quality but extremely light on disk space (and just as importantly, I/O). But I'm not fooling myself, my final edits are still 4th gen at best when I edit in ProRes-422, but they look damn good in my opinion.
VJ Justin Allen 7:13 PM - 17 December, 2007
Quote:
Quote:
One thing I haven't seen in this thread is that the images that you will be ripping from existing DVD's and then compressing again, will be 3rd generation compressions. The quality will not be that good, especially when put on a larger screen or projector.


4th generation for anyone doing edits (without rendering to uncompressed first). i've pointed this out to a few people I know who are doing edits. The least you can do is rip to uncompressed, do your edits then render to final output. That way you don't lose a generation.

Quote:

Also I would imagine an issue with using MPEG2 would be the GOP structures. How is Serato going to handle them?


i imagine that serato will use the decoded frames directly from memory (like VDJ does), so they are not concerned about I, B frames, GOP struct, etc. Each frame is fully rendered in memory and that's what you see on the screen. it's a guess but that's the only way I could envision anything even resembling decent scratch performance being usable.

Also, i'll challenge you to stand on the dance floor and tell the difference between the VOB ripped directly from DVD and my H.264 encode of the same video. I'll blind test you one against the other and you can try and tell me which is which. I challenge you.


The problem with each frame being fully rendered is that in hardware based solutions there is a dedicated chip that does all that heavy work. In computer based syetems unless your video card has an mpeg chip on it, it has to do that via software...and that means dropped frames, slight pauses and audio dropouts.

And as to the challenge, I'm new to this site and would like to play nice for just a little while longer. But I promise you that I could tell the difference.
VJ Justin Allen 7:16 PM - 17 December, 2007
Quote:
yes h.264 is that good

imagine if we could rip it from the beta tapes instead of ripping from a dvd.

swift what bitrate do u use for the video?


Most videos are now done using film or HD. Mostly because that is a digital format. Beta is an analog format, hence you get a poorer quality on beta vs digital.

And there are encoder cards out there that do live, real-time H264 encoding. Once again, it will be up to companies like Promo Only to see that the Serato (and others like it) as a viable solution before they also come out with alternative versions of their video subscriptions.
D-Twizzle 7:22 PM - 17 December, 2007
I'm glad I can edit my mpeg/vobs directly in sony vegas without converting to another format first.
a-swift 7:23 PM - 17 December, 2007
Quote:

And as to the challenge, I'm new to this site and would like to play nice for just a little while longer. But I promise you that I could tell the difference.


that sounds like a challenge accepted to me. don't worry though, the last guy to accept a challenge from me will end up costing me $50 (fucking CELTICS!). and while you *might* be able to tell the difference between VOB and my H.264 on certain scenes, there's no way that anyone would ever say VOB are worth twice the disk space usage for very minimal visual improvement, especially considering laptop hard drives top out at 320GB.
djsteel 9:11 PM - 17 December, 2007
I completely agree with A-Swift, we both have done a lot with video and big ass screens and I've found some really good compression solutions. I actually convert all my Promo Only vids to Divx and end up going from about a 1 gig files to about 50 mb files and no one can tell. I've never once been told by anyone including Promo Only that my video look bad. I do demonstrations for both Promo Only and Pioneer.

Here's the spec's on my normal compression rates.



***********************************************************
/Users/kris/Desktop/(Get Up I Feel Like Being A) Sex Machine - Brown, James (109).avi
Length(s) 306.29 (Samples: 183772, Timescale: 600)
Size 75.15 MB
Movie Tracks:
VideoType: DX50, 720x544
0x44583530
Audio Tracks:
AudioType: .mp3 (48000kHz, 16bit)
0x2e6d7033
Frame rate: 29.97 per second
Keyframes: 1434 (min: 1, max: 240,avg: 6.4)
VJ Justin Allen 9:27 PM - 17 December, 2007
OK, you can agree. The fact is is that they will look different if for no other reason other than you have transcoded an mpeg which has already been encoded once before.

Put this image on a 2000 luman plus projector like the NEC NP40 or NEC NP50 and you will see these issues.

The blacks will be crushed and you have introduced other issues into the image.
The typical Promo Only mpeg file is approx 200mb or so. The same length file (in beta format) will be approx 60 - 80 gig. (approx 21 gig per minute).

This is what make the compression issues so important. All everyone here is doing is transcoding or recompressing. That will not be the long term answer.

Guys, I promise I am not attacking, just explaining.
D-Twizzle 9:40 PM - 17 December, 2007
Quote:
The blacks will be crushed and you have introduced other issues into the image.

I can agree with Justin on this. Videos with a lot of dark scenes come out like crap. One example I can think of is Omarion's Icebox. I made an upbeat dance version of that song and it doesn't look that great. Try transcoding that even at 3mbps mp4 and it will come out a little blocky. It's still good to play in the club, but you can visually see tell the difference, even on a small screen.
djmelny 10:29 PM - 17 December, 2007
sooo whats better for big screens guys divx or MPg4
a-swift 12:45 AM - 18 December, 2007
Quote:
sooo whats better for big screens guys divx or MPg4


big screens or not, H.264 is probably a better choice in all categories except for maybe encode time, regardless of scren size.
Serato, Support
Matt G 2:54 AM - 18 December, 2007
Quote:
sooo whats better for big screens guys divx or MPg4


Heh. DivX *is* MPEG4. DivX is a specific implementation of the MPEG4 codec spec. You probably want to compare MPEG4 (or DivX or Xvid) to H.264. H.264 has noticeably higher quality.
a-swift 7:52 AM - 18 December, 2007
Quote:
Quote:
sooo whats better for big screens guys divx or MPg4


Heh. DivX *is* MPEG4. DivX is a specific implementation of the MPEG4 codec spec. You probably want to compare MPEG4 (or DivX or Xvid) to H.264. H.264 has noticeably higher quality.


Uhh. Hmpph. I think what I said is what he said. Either way, you should be seriously considering this: "how can I make my workflow accommodate the h.264 codec".

once you do that, you'll find what's good. it's hidden beneath the surface. forego the nonsense. concentrate on what's real. what works today.
djsteel 2:32 AM - 20 December, 2007
Yeah I'm gonna reconvert everything again. I've done a couple and I still think the example I gave above is good, but I've noticed that h.264 seems to be the social consensus so I'm gonna switch em.