Compression - Please point me in right direction at DVinfo.net

Bob Warner · January 2nd, 2008, 07:39 PM

No response on my last post - must have said something stupid, or poorly - or everyone is just off enjoying the holidays.

Just don't like the youtube quality, so I looked into BitTorrent. I'm a newbie - know nothing about compression. Shooting cycling video with Canon HV20, and editing in iMovieHD 6. Just being a dad and supporting my son's cyclocross team by shooting video. (Cyclocross is sort of road biking in a park on a course laid out with yellow caution tape, barriers, mud, sand, rain, snow,etc. - big in Europe but nothing here.)

Went to Vuze.com and downloaded a 3 minute Standard Def 36MB Warren Miller ski video which looks very good full screen on my MacBook Pro (2.33 GHz). My 3 min. HD iMovie is about 6GB. If I "share" to a Quicktime Movie (H. 264, Frame Rate:30, Data Rate: Automatic, Size: 1280X720, Sound AAC/48000/128) I get either a 1.5GB file (Compression quality: "best") or a 55MB file (Compression quality: "least"). Neither one looks any good full screen size - the left-right motion of the cyclists turns them into lots of out-of-register horizontal lines (imagine an 8X10 photo sliced into 200 strips and then take the odd numbered strips and move them all 1/16 inch to the right). At about 1/4 screen size (Quicktime menu calls this "half size") they both look okay, with the "best" quality compression showing better detail in the unmoving landscape. So the Miller SD 36MB video is about 1/40th the size of mine and looks sharper - the motion shots are clear.

As I said, I'm a newbie. I know Warren Miller is starting out with better footage (film maybe), but still the Canon footage is pretty sharp. Is he just using much better compression software and/or something else?

I've been reading up a bit on Compressor 3, Sorenson Squeeze, Episode 4.4, and Flix. I don't want to waste money, but I have the bucks if one of these is a solution. I'm hoping, perhaps foolishly, that I can take my iMovie and drop it into a software compression "machine" that I can properly configure (through experimentation or consulting a pro) that will spit out a movie (Quicktime, Flash, whatever is best - I don't care how long it takes) that will not be too huge, so I can then upload it to a BitTorrent site and others can download it in less than a lifetime. I'd at least like it to look great at 1/4 screen size if that's possible.

Or if I'm hopelessly delusional on this topic and need to get "edjumacated" then maybe someone could point me towards a book or maybe there are some technical schools around where I could learn a few things (I'm in the LA area). Okay, thanks. Bob

Seun Osewa · January 2nd, 2008, 08:01 PM

You should definitely convert to SD resolution (640x480) or less and compress with the h.264 codec. You should be able to do that with Quicktime PRO. What I would use is definitely far more complex (various open source programs). After dong that, you can host the video with www.blip.tv, for free.

Herman Van Deventer · January 6th, 2008, 05:20 PM

BOB /

There are various methods for better compression results on the forum.

Jason's thread - http://dvinfo.net/conf/showthread.ph...ht=downconvert

is the key to understanding better resize and compression.

Greetings.

Bob Warner · January 9th, 2008, 05:51 PM

Thanks for responses. Dang - I searched but never found that thread Herman. Thanks very much! Bob

Alessandro Machi · January 13th, 2008, 03:46 AM

What I am discovering is once you make a compressed file, DO NOT recompress it, or game over.

January 2nd, 2008, 07:39 PM	#1
Bob Warner Regular Crew Join Date: Mar 2007 Location: Los Angeles, CA Posts: 35	Compression - Please point me in right direction No response on my last post - must have said something stupid, or poorly - or everyone is just off enjoying the holidays. Just don't like the youtube quality, so I looked into BitTorrent. I'm a newbie - know nothing about compression. Shooting cycling video with Canon HV20, and editing in iMovieHD 6. Just being a dad and supporting my son's cyclocross team by shooting video. (Cyclocross is sort of road biking in a park on a course laid out with yellow caution tape, barriers, mud, sand, rain, snow,etc. - big in Europe but nothing here.) Went to Vuze.com and downloaded a 3 minute Standard Def 36MB Warren Miller ski video which looks very good full screen on my MacBook Pro (2.33 GHz). My 3 min. HD iMovie is about 6GB. If I "share" to a Quicktime Movie (H. 264, Frame Rate:30, Data Rate: Automatic, Size: 1280X720, Sound AAC/48000/128) I get either a 1.5GB file (Compression quality: "best") or a 55MB file (Compression quality: "least"). Neither one looks any good full screen size - the left-right motion of the cyclists turns them into lots of out-of-register horizontal lines (imagine an 8X10 photo sliced into 200 strips and then take the odd numbered strips and move them all 1/16 inch to the right). At about 1/4 screen size (Quicktime menu calls this "half size") they both look okay, with the "best" quality compression showing better detail in the unmoving landscape. So the Miller SD 36MB video is about 1/40th the size of mine and looks sharper - the motion shots are clear. As I said, I'm a newbie. I know Warren Miller is starting out with better footage (film maybe), but still the Canon footage is pretty sharp. Is he just using much better compression software and/or something else? I've been reading up a bit on Compressor 3, Sorenson Squeeze, Episode 4.4, and Flix. I don't want to waste money, but I have the bucks if one of these is a solution. I'm hoping, perhaps foolishly, that I can take my iMovie and drop it into a software compression "machine" that I can properly configure (through experimentation or consulting a pro) that will spit out a movie (Quicktime, Flash, whatever is best - I don't care how long it takes) that will not be too huge, so I can then upload it to a BitTorrent site and others can download it in less than a lifetime. I'd at least like it to look great at 1/4 screen size if that's possible. Or if I'm hopelessly delusional on this topic and need to get "edjumacated" then maybe someone could point me towards a book or maybe there are some technical schools around where I could learn a few things (I'm in the LA area). Okay, thanks. Bob

January 13th, 2008, 03:46 AM	#5
Alessandro Machi Major Player Join Date: Oct 2003 Location: Los Angeles, Ca USA Posts: 553	What I am discovering is once you make a compressed file, DO NOT recompress it, or game over. __________________ https://alexlogic.blogspot.com/ Los Angeles Emmy Winner (yes, used a video edit controller and loved doing so.)

January 2nd, 2008, 08:01 PM	#2
Seun Osewa Major Player Join Date: Oct 2006 Location: West Africa Posts: 255	You should definitely convert to SD resolution (640x480) or less and compress with the h.264 codec. You should be able to do that with Quicktime PRO. What I would use is definitely far more complex (various open source programs). After dong that, you can host the video with www.blip.tv, for free.

January 6th, 2008, 05:20 PM	#3
Herman Van Deventer Major Player Join Date: Nov 2006 Location: cape town South-Africa Posts: 251	BOB / There are various methods for better compression results on the forum. Jason's thread - http://dvinfo.net/conf/showthread.ph...ht=downconvert is the key to understanding better resize and compression. Greetings.

January 9th, 2008, 05:51 PM	#4
Bob Warner Regular Crew Join Date: Mar 2007 Location: Los Angeles, CA Posts: 35	Thanks for responses. Dang - I searched but never found that thread Herman. Thanks very much! Bob