compression

[Bill Totolo]

I just compressed a 4 minute video using Apple's H.264 and got it down to 32mb.

I need to upload this to a website that limits uploads to 8mb.

 

What's the most efficient way to do this while maintaining some quality?

The other videos on the sight look pretty decent.

 

Thanks

[Phil Rhodes]

You are unlikely to do much better than the H.264 you're already using - all you can do is decrease the bitrate and ensure you're using the most careful encoding options - multi-pass, high search precision, etc. Anything that makes it take longer to encode is probably your friend; really, seriously good H.264 encoding traditionally takes tens of times longer than realtime, although if you're doing it on an eight-core Mac Pro then it'll probably be fairly rapid regardless. At the end of the day, though, you're at the mercy of the content. If this is the music video I saw while I was in LA, you're probably in fairly decent shape as it won't need a lot of bandwidth to encode the white graphical elements.

 

There are theoretically slightly better H.264 implementations than Apple's, but you don't really want to use them as you'll want your output to be playable by Quicktime.

 

Phil

[Walter Graff]

Try Sorensen 3 or FLV. Bottom line 8 gig limit means H264 just will not cut it.

[Phil Rhodes]

Um... Flash Video uses the Sorenson Spark codec, a variant on H.263, which, as the number suggests, is a precursor to H.264 and lacks many of the refinements therein. Sorenson 3 is the precursor to Spark and is therefore presumably more primitive than it.

 

It may simply be that the Spark and Sorenson 3 compressors have more conservative default settings or presets, or use more post-processing in the decoder, which give the impression of higher performance. It's very difficult to be objective about any of this without looking at side by side comparisons at the same bitrate from the same source, but H.264 should outperform any of them.

 

Phil

[Bill Totolo]

I'm finding that bit rates as low as 125kbps look amazingly satsifying @ 320x240 and only take up about 9mb. Thanks for the insight.

 

Wikipedia also led me to a lot of info on all the various codecs out there, which I was sorely under informed about.

 

Cheers.

[Walter Graff]

Phil I don't think you got the gist of my post. I often equate the web with the influx of these new-fangled prosumer HD cameras. Folks want to spend $5k on an HD camera but want $100k performace. And with the web folks also want motion picture projection quality on limited bandwitdh. I belive the person who asked thde question mentioned that he tried his best with the AVC codec and got it down to 30 megs but the limit is 8. So I suggested he try an engine that is not as heavy on the space fulfillment. Sometimes you simply are not going to be able to squeeze ten gallons of water in a five gallon bucket without giving up something. I faced a similar problem last year working for a major pharmaceutical company. I had produced some high def productions that were to be delivered to the web. They were to go out to all sales people. All was good and I got my programs (usually 3 to 4 minutes in length) down to a reasonable size that I knew was acceptable. Then the tech folks said that I had a limit of ten megs per piece. Partially because of their servers and partialy because the sales force was using these newfalngeld tapblet PC that didn't have great video cabability. Okay... So in the end I had to use a lesser compression engine but used a setting that offered me nearly as good preproduction while still fitting into the needs of the tech department. Sometimes folks think that the only way they can make a quality web movie of 300pixels in size is to use compression schemes that are far greater than the output will need to be. AVC is a labor intensive codec and while it works for some applications, is far too much for others. You have to weigh where its going, what it's purpose is and like these endless discussions of cameras, if the end result is really going to make a difference or just satisfy ego and bottleneck someones computer.

[Phil Rhodes]

Well yeah.

 

But it'll still look better at a lower bitrate with AVC.

 

Phil

[Tom Lowe]

H.264 is badass.

 

I also find that the ever-improving WMV codec can be very impressive with some types of footage, though it is considered a lesser format.

[Walter Graff]

H.264 is badass.

 

I also find that the ever-improving WMV codec can be very impressive with some types of footage, though it is considered a lesser format.

 

 

I think you are absolutely right. While not a Windows person, I often have to make WMV for various clients and the perceived quality is exceptional. What many folks don't realize is that while codecs are standards once they are introduced, they are continually imporroved. Just like folks who say MPEG-2 is an old codec. But the MPEG-2 used today is not the same MPEG-2 of years past.

[Tom Lowe]

I think WMV gets a bad rap because it is associated in many people's minds with crummy web videos.

 

Maybe MS should rebrand their codec with a catchier name, like XCodec or something. :)

[Tim O'Connor]

Phil I don't think you got the gist of my post. I often equate the web with the influx of these new-fangled prosumer HD cameras. Folks want to spend $5k on an HD camera but want $100k performace. And with the web folks also want motion picture projection quality on limited bandwitdh. I belive the person who asked thde question mentioned that he tried his best with the AVC codec and got it down to 30 megs but the limit is 8. So I suggested he try an engine that is not as heavy on the space fulfillment. Sometimes you simply are not going to be able to squeeze ten gallons of water in a five gallon bucket without giving up something. I faced a similar problem last year working for a major pharmaceutical company. I had produced some high def productions that were to be delivered to the web. They were to go out to all sales people. All was good and I got my programs (usually 3 to 4 minutes in length) down to a reasonable size that I knew was acceptable. Then the tech folks said that I had a limit of ten megs per piece. Partially because of their servers and partialy because the sales force was using these newfalngeld tapblet PC that didn't have great video cabability. Okay... So in the end I had to use a lesser compression engine but used a setting that offered me nearly as good preproduction while still fitting into the needs of the tech department. Sometimes folks think that the only way they can make a quality web movie of 300pixels in size is to use compression schemes that are far greater than the output will need to be. AVC is a labor intensive codec and while it works for some applications, is far too much for others. You have to weigh where its going, what it's purpose is and like these endless discussions of cameras, if the end result is really going to make a difference or just satisfy ego and bottleneck someones computer.

 

 

Video for the web isn't my forte although I do it, and use various compression methods, so my question may

be a bit naive but people often tell me that they don't want to shoot HD if they're making a web video.

 

Why did you shoot HD for the pharmaceutical shows?

 

Of course I know that something shot on HD or 35mm. or whatever really good format is going to look

better than a trailer that was shot with a student's one chip Mini-DV camera, but in your case was it

a choice between HD or really good SD? Why go with HD if it were for the web? Where there other

destinations, say HD screenings, for the same content? Thanks.

[John Sprung]

Why go with HD if it were for the web?

As a general rule, shoot, post, and archive the best you can afford. Downconvert to what you need to deliver. That way you're covered if the project gets sales in some market you didn't anticipate.

 

 

 

-- J.S.

[Tim O'Connor]

As a general rule, shoot, post, and archive the best you can afford. Downconvert to what you need to deliver. That way you're covered if the project gets sales in some market you didn't anticipate.

-- J.S.

 

That makes a lot of sense. Thanks.

[Walter Graff]

Why did you shoot HD for the pharmaceutical shows?

 

There is absolutely no reason to use HD over SD for a web presentation. You gain nothing. In my case I did so because I was making 4x3 400x300 movies and the extra size of my origional allowed me to crop, and pan and scan my finished piece to accomodate graphics and titles on screen along with the video. In other words I shot everthing centered in 16x9 and was able to manipulate the picture later into the 4x3 space depending on where the graphic elements needed to be.

[Tim O'Connor]

There is absolutely no reason to use HD over SD for a web presentation. You gain nothing. In my case I did so because I was making 4x3 400x300 movies and the extra size of my origional allowed me to crop, and pan and scan my finished piece to accomodate graphics and titles on screen along with the video. In other words I shot everthing centered in 16x9 and was able to manipulate the picture later into the 4x3 space depending on where the graphic elements needed to be.

 

 

I guess if you're absolutely, positively doing something for the web only, why break out the HD camera but if

it's a short that might end up becoming web popular and go on from there, and it's not insane to shoot HD

on that production, then maybe it would be something to consider. Thanks.

[Jess Haas]

Before you know it people will be demanding higher resolution web delivery so even if something will only be shown on the web shooting HD is good future proofing. There is actually a surprising amount of video starting to pop up on the web in HD resolution.

 

~Jess

[Walter Graff]

Before you know it people will be demanding higher resolution web delivery so even if something will only be shown on the web shooting HD is good future proofing. There is actually a surprising amount of video starting to pop up on the web in HD resolution.

 

~Jess

 

Sharpness is a psycho-visual sensation proportional to the square of the area under a curve plotting contrast ratio against detail fineness. In simplest terms, there is no such thing as a 500x200 pixel wide movie in HD. If the delivery is for transfer to a larger viewer (something that doesn't happen now) than perhaps HD is viable but for normal web viewing (small managable files) and with the nominal maximum resolution of 22 CPD that a person can percive, HD is a gimmick when it comes to web distribution and has little practical use now or in the percievable future. If a web movie was made for other means of distribution where the need for higher resolution is valid (a larger screen and a nominal viewing distance), then shoot in HD, but if its for web-only distribution, HD is nothing but a marketing term that will cost you far more bandwidth than most people care to wait around for, and little more than what you'd get with an SD counterpart.

 

While these HD aquired movies below would enjoy playback on a large HD monitor, viewing it as a little web movie shows little more than what SD does in the same movie. Of course if it was viable to send people 100meg full HD size web movies, then there would be an advantage viewing-wise, but we can't today nor wil we in the forseeable future.

 

http://www.bluesky-web.com/GV-07-FIN.mov

 

http://www.bluesky-web.com/daytona002.mov

 

http://www.bluesky-web.com/gloshow3.mov

[Tom Lowe]

Does anyone know: Is H.264 an evolving codec? Are changes and improvements made to it periodically?

[Walter Graff]

Does anyone know: Is H.264 an evolving codec? Are changes and improvements made to it periodically?

 

All codecs evolove. The standerds of a codec are set in the begining and then over time as technology imporves and more people utilize a codec, the headrom set with that codec is utilized. That is the evolution. For instance H.264 has the ability at 4096x2304@26.7 FPS 4:4:4 at 960 Mbit/s, but we are not there yet as no one has implimented such a need or system, but when and if we do, it will be there.

[Tom Lowe]

Interesting.

 

I do seem to notice that I get better results with H.264 now than I did about a year ago. I wasn't sure if the codec had improved, or whether I might be doing something different.

[ross e lea]

"Sharpness is a psycho-visual sensational proportional to the square of the area under a curve plotting contrast ratio against detail finen..."

 

 

 

iS tHis eNgliSh???

[Walter Graff]

"Sharpness is a psycho-visual sensational proportional to the square of the area under a curve plotting contrast ratio against detail finen..."

 

 

 

iS tHis eNgliSh???

 

 

Yes, it's a description of what is called MTF or Modulation transfer function and is the single most important term that describes in simplist terms how you see a picture and percive its sharpness.

[Phil Rhodes]

Yes.

 

The thing is it's difficult or impossible to apply MTF to a modern video codec. It's dependent on... well... everything. What the picture content is, has recently been, and will soon be; how much hard work you're willing to make the decoding and encoding devices do; what the conduit between them is capable of.

 

It's hopelessly subjective.

 

Phil

[Walter Graff]

It's hopelessly subjective = Sharpness is a psycho-visual sensation proportional to the square of the area under a curve plotting contrast ratio against detail fineness.

 

It's one of the reasons why Sony gets away with 1440 as opposed to 1920. HD is in your head, has to do with the screen size you are looking at, the distance you are from it and the limit of human eyesight to see contrast. Outside of that, it's your minds interpretation.

[Phil Rhodes]

There are quite a lot of people in the world, me among them, who would enthusiastically contend that Sony don't get away with 1440.

 

Phil