I've played around a bit with H.264 and discovered a couple of things that made me think that it's not quite ready for wide usage.
One is the Quicktime 7 requirement, which you mentioned. And this is a problem that will resolve itself over the next 6 months as the userbase grows. The other problem is the shear processing power that it takes to decode and play h.264. My newer G5 can play them well, of course, but my wifes 2 year old ibook chokes on them. My old G4 even has some problems with them. So my attitude is that if even computers that were made only 2 years ago can't handle playing h.264 files then I'll wait a couple of years before I start using the format much. On top of that, the encoding times are much longer than encoding in other formats, and the end result isn't a lot better than MP4 at simular data rates and file sizes IMO. So bottom line, I have no use for h.264 for the time being. Bill Streeter LO-FI SAINT LOUIS www.lofistl.com --- In [email protected], Lynn Lane <[EMAIL PROTECTED]> wrote: > Richard, > > I'm right there with you. My first post has pretty poor compression/ > video quality. I use FCP 5 and Compressor 2. I tried to follow along > with the Freevlog info but it is geared towards Compressor version 1, > which is understandable since most people have that. Anyway, I posted > something on the Apple Compressor forum and got this response. My > initial question was regarding how to get my vlogcast video to look > closer to what I have when I export for DVD. Here's the response. I > used something similar to the response for my second post on my blog > and there is truly a significant change in quality. One important > thing to note is that the audio quality selection has nothing to do > with end all size, only time to compress, so I suggest choosing a > high quality setting for your audio and accept the minimal change in > compression time. > > Here's the response: > > "Unless you use H.264 you aren't going to get DVD quality levels > unless you use DVD-like bit rates (5Mbps to 7Mbps). Video codecs like > MPEG4 and Sorenson will help a little but H.264 is the only codec > that Apple supplies that will generate notably smaller files while > retaining quality levels that approach those of a DVD. > > However, H.264 is only available on systems running QuickTime 7 and > therefore there are a limited number of people who can actually view > H.264 movies. In any case, even with H.264 the files and data rates > are not going to be dramatically smaller. > > With H.264 and depending upon the subject you might see a reduction > by one half in data rate for roughly DVD quality. But you'd still be > talking rates in the 3Mbps to 4Mbps range for a video that was 640 x > 480 in size. Of course, you could go to a size of 320 x 240 which > could reduce the needed data rate by about a factor of 4, then you'd > be down into the 750Kbps to 1Mbps range. > > Thus, for a 320 x 240 size movie using H.264 and AAC audio you'd be > able to create a one minute movie that was about 6MB in size. Then, > you could reduce that even further by using a lower frame rate -- > something like 15fps. > > Here is a setting that will produce fair quality at a movie size of > 320 x 240 with mono AAC audio: > > Frame Size: 320 x 240 (this assumes a starting NTSC 4:3 DV source at > 720 x 480) > Frame Rate: 15 fps > > Best Quality (multi-pass) H.264 video > Key Frame Every 60 frames > Optimized for Download > Video Data Rate: 384Kbps > > Audio Data Rate (AAC, mono): 32Kbps > Audio Sample Rate: 24KHz > > Estimated file size for one minute movie: 3MB > > Your mileage may vary and for clients with dial-up internet service > this format will probably still be too large. It's also not going to > be anywhere near DVD quality (think extended play VHS tape quality). > If the quality proves to be unacceptable then up the data rate to > 512Kbps while still maintaining the 320 x 240 and 15fps settings. > > A clean, high-quality deinterlace operation will also produce better > results if you are working from an interlaced DV source. If you are > going to reduce the size of your video, cutting the vertical > resolution (height) of the interlaced source by exactly one half will > produce a deinterlaced effect (for example, with NTSC DV vertical > resolution is 480, so a good size reduction would be 480 / 2 = 240). > Of course, for display on a computer monitor it is best to start with > a natively progressive (non-interlaced) source. > > As a point of comparison, you can note that the music videos that are > on the iTunes Music Store generally run in the 1.5Mbps range (using > Sorenson Video 3 codec, AAC stereo audio, with frame sizes around 480 > x 300 at 29.97 fps)." > > Good Luck. > > Lynn > http://docmaker.blogspot.com > > > On Oct 5, 2005, at 9:39 AM, Richard wrote: > > > I tried the follow the directions from freeVlog for compression > > with final cut pro > > > > http://freevlog.org/wordpress/index.php/2005/05/24/55/ > > > > My version of final cut pro is 5.0 > > > > 1) I did not have an option in the audio format settings for Mpeg 4 > > audio, which is what she selected so I selcted AAC with the > > defaults and it seemed to work fine > > > > 2) I used freevlog's video settings > > > > .... MPEG-4 Video > > .... Key Frames every 5 frames > > .... Data rate restrict to 60 kbits/sec > > .... Compressor Quality (originally medium, but I changed to best) > > > > ... it is really small by my standards (7.6 MB for 5 minutes) > > ... it looks REALLY bad, even after changing the compressor quality > > to best > > > > ... I can, of course, play with settings systematically forever, > > but I'm just wondering what single setting can I change that will > > most directly increase the quality > > > > ... once again, any help appreciated! ... thanks ... Richard > > > > -- > > Richard > > http://www.richardshow.com > > YAHOO! GROUPS LINKS > > > > Visit your group "videoblogging" on the web. > > > > To unsubscribe from this group, send an email to: > > [EMAIL PROTECTED] > > > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Fair play? Video games influencing politics. 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