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Choosing a output codec
Hello, how do I choose a output codec? Like, someone have information about what each one do?
I need to make a game trailer, and upload to several places with .flv support (like, Youtube, Vimeo…)
I tried MP4 but it looked strange, a part that simulate old TV (with scanlines and noise), compressed strange, with bands of “black stuff” randomly changing their position every few seconds. Also, the gameplay lost some quality (it use vector-looking graphics, or neon… or something like that), with the thin lines (that compose most of the graphics) becoming a bit blurry.
What I can do to improve, find a better codec, or throw more mbps on the mpeg-4? (I used variable bit rate, maximum 4Mbps, average 700Kbps)
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4 Replies
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The 700Kpbs is what’s killing you. Bump it to 10Mpbs. Let YouTube knock it down when they convert to Flash. It’ll cost you more in upload time but give you significantly greater quality.
Douglas Spotted Eagle
VASSTCertified Sony Vegas Trainer
Aerial Camera/Instructor -
It sounds like you’re on the right path with MPEG4 but 4Mbps max with 700Kbps average is way too low if you want high quality. I would use 6Mbps max with 3Mbps average. If you want more quality, you have to increase the average bit rate.
~jr
http://www.johnrofrano.com
http://www.vasst.com -
Yep, throwing the bit rate upward made it waaay better…
Now this I never figured: What difference it make to use two passes, or not?
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What difference it make to use two passes, or not?
It could be significant because two passes will optimize the allocation of bits:
With a one pass encode, the encoder guesses at how many bits it can use for any particular frame and because it has no idea how many bits it will need in the future, it is usually pessimistic because it knows it can’t go over the average.
With a two pass encode, the encoder analyzes the entire video in the first pass building a plan for how it can best allocate the bits it has and still maintain the average. Because it can optimize the plan across the entire video, it usually produces superior results in the second pass for any bit rate below what is fully needed to represent every frame. The only downside is that it takes twice as long to encode.
~jr
http://www.johnrofrano.com
http://www.vasst.com
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