2338 Views 8 Replies Latest reply: Oct 12, 2005 12:03 PM by Big Burro
It's hard to tell if the times you are reporting are unusual since it depends greatly on the amount of rendering you are doing and whether you are exporting directly to Compressor from Final Cut Pro. Encoding times will usually be shorter if you first export your sequence as a QuickTime Movie using Current Settings, with DVD SP markers included, and as a reference movie (not self-contained). Then bring that export into Compressor and start the job from there.
You might also want to try one-pass encodings since they are much faster and still provide good quality.<small><hr width="75%"><small>If this suggestion helps in any way, a confirmation or acknowledgment would be appreciated, since that would also help others who may be having the same difficulty. Do for others as you would have them help you.<center>Thanks for sharing, Waymen.</center></small>
I've heard some good things about FastCoder, but we should really compare "Apples-to-Apples." While it's true that FastCoder can work in realtime it is by its very nature a one-pass device and if you use Apple's Compressor application in a so-called "fast" one-pass mode you can also encode MPEG2 in realtime. In fact, on a G5 you can do faster than realtime.
For example, using Compressor 2.0.1 on my lowly 800MHz PowerBook I can encode one-pass MPEG2 with PCM audio in a time ratio of 1.4:1 (admittedly slower than realtime). However, given that data I'd estimate that you could do near realtime encoding on a 1.25GHz G4. Thus, it should be possible to approach realtime MPEG2 encoding on any currently shipping G4 Macintosh -- Mac mini, eMac, iBook, etc.
It is true, however, that Compressor's best quality, two-pass encodings can take a very long time (over ten times the above example). So, you've got a tradeoff when using Compressor, do you want fast encoding or best quality?
I understand that FastCoder produces very nice output, so I'm not suggesting that the quality you will get with that product will be below what you could achieve with Apple's Compressor. However, when you compare encoding times you also need to consider tradeoffs between the encoding method and the quality of the output.
FastCoder certainly offers some advantages over software-only encoders, but I suspect that "Apples-to-Apples" it won't save you that much time if you have a G5 or one of the faster G4 systems.
I would be very interested if anyone else can render in close to real time with Compressor using one-pass MPEG-2. Here's my project:
One hour HDV Doc
Dual 2.5 w/ 8 gig ram and an s-ata box o drives,
Maybe its because I am going from HDV to MPEG-2 but the encoding time is right at 10-1. Meaning it takes 10 hours to encode one hour. If anyone has a different faster story PLEASE advise. What can I check to see if my system has a chink in it?
Yes, HD will make a significant difference. I was talking about standard definition DV. If I can do standard definition one-pass MPEG2 in a ratio of 1.4:1 (one hour of input takes about 85 minutes to output) on my 800MHz PowerBook then I'm sure a Power Mac G5 could do better than realtime on SD material.
Also, the best quality Frame Controls in Compressor 2 are very slow. So if you are doing any type of rate conversion, deinterlace, or resize using Compressor's Frame Controls then expect long processing times.
One thing I just noticed last night. I have normally compressed all my DVD content at 29.97fps with lower field dominance.
Last night I realized I could output my current project as 23.98 progressive and run it through compressor in that format. The compression time was cut in half. Now, there are 1/6t less frames to compress, but I think it's the lack of fields that sped it up the most. Never realized it would have made such a difference in processing speed.
As a bonus to all of it too, get a little more quality on each frame due to the slower frame rate, as well as progressive output. Going to make sure I do any film footage this way again.
Better yet, invest in PAL camera, 25 fps has tons of advantages, better image quality because of reduced frame rate as compared to that unnecessarily high 29.97 in NTSC and more film like look to it among others. Also no need to fight pulldowns with film material. Compressor can transcode your final output to NTSC if so desired.