Cutting a trailer from DVD source of SD program for You Tube – best workflow?

[Rafael Amador]

Codecs are basic sets of rules and allow many variations.
Probably the default H264 specs on Squeeze are better fine tuned than in Apple’s codec.
Don’t use CBR. Limit the data rate and always set Key-Frames=AUTO and Multipass.
rafael

[Jayasri (joyce) hart]

True–I am beginning to understand codecs. Before I read your message, I read Shane Ross on the subject and tried his workflow for mp4:

https://forums.creativecow.net/readpost/8/1175068

MPEG Streamclip produced the best result!

As for CBR, I thought that since my short video didn’t have too many variations in video material (eg. high action, motion graphics etc) I could get a faster encode and the same quality.

Now that I have your attention, let me ask about a You Tube tip I read in Jan Ozer’s article “Encoding for You Tube How to Get the Best Results”(https://www.streamingmedia.com) In the footnote, I found: “It is ideal to use constant quality encoding. This will let you create a high quality variable bitrate file, at the speed of a single pass. It will maintain a consistent quality throughout the file, rather than trying to allocate bits to an arbitrary bitrate, which can easily undershoot or overshoot, and with two pass, take extra long to create.”

The tip seems to be from Colleen Henry, Video Hacker, Google Video Infrastructure. I’m not sure what “constant quality encoding” refers to. Your answer might be helpful to other Forum folks.

[Rafael Amador]

[Jayasri (Joyce) Hart] “This will let you create a high quality variable bitrate file, at the speed of a single pass. It will maintain a consistent quality throughout the file, rather than trying to allocate bits to an arbitrary bitrate, which can easily undershoot or overshoot, and with two pass, take extra long to create.””
Well, but is not all about allocating bits.
To get good quality, as important as the data rate are the key-frames.
You may know which is the correct data rate but you have not an idea of the optimal sequence of key-frames your movie needs to get the best compression.
Multipass process will set the proper amount of key-frames and get the best out of the data rate.
rafael

[Jayasri (joyce) hart]

Thanks, Rafael. This is important for us to understand.

[Sascha Engel]

I just had a similar job not too long ago.
I did some side by side tests and I can tell you for sure ProRes LT for this is way enough, even for Color Grading.
I also realized, that MPeG Streamclip is good and fast, but has a tendency to darken the footage and shift the colors a bit. Just take that into account.

Greetings,

Sascha Engel
TIME BANDITZ Productions
http://www.youtube.com/taikang