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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 On Oct 5, 2005, at 9:39 AM, Richard wrote: I tried the follow the directions from freeVlog for compression with final cut pro YAHOO! GROUPS LINKS
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- Re: [videoblogging] final cut pro compression woes Lynn Lane
