April 8, 2013

Render time experiments on Sony Vegas 9

My computer specs:
Pentium Dual Core E5200 @ 2.5 Ghz
Nvidia 210 1GB
2GB of RAM
SATA HDD 7200rpm

SAMPLE CLIP USED: 1080p video with contrast correction applied (no audio)

Rendered to: mp4, 1440x1080, 30fps
RENDER TIME (6mbps) 3:32 FILESIZE 13.1 MB
RENDER TIME (3mbps) 3:32 FILESIZE 6.73

Rendered to: mp4, 1280x720, 30fps
RENDER TIME (6mbps) 2:24 FILESIZE 13.1 MB
RENDER TIME (3mbps) 2:38 FILESIZE 6.73

Rendered to: wmv, 1280x720, 30fps
RENDER TIME (4.8mbps): 3:43 FILESIZE 11.7MB

Mp4 bitrate DOESN'T affect render times.
Lower resolutions render FASTER.
WMV renders SLOWER than Mp4
Rendering to 6mbps produces twice the filesize of a 3mbps render
Extra observations: 3mbps has more video artifacts than 6mbps

SIDETRACK: Relationship of length, bitrate, and filesize
FORMULA: filesize = videolength * bitrate

All tests are rendered to mp4 720p 30fps 6mbps (and all other default Vegas 9 settings)

Motion blur tests
TEST1: with motion blur (2:24)
TEST2: no motion blur (2:27)
CONCLUSION: motion blur has no significant effect on render time.
Extra Observation: motion blur may cause video ghosting

Resampling tests:
NOTE: motion blur is ENABLED. SAMPLE CLIP is not speed up or slow down.
TEST1: smart resample (2:24)
TEST2: no resample (1:42)
CONCLUSION: disabling resample speeds up rendering up to 30%

Chroma Key tests
Chroma settings: black, high: 0.169
TEST1: unmasked chroma 5:28
TEST2: masked chroma 5:17
CONCLUSION: masking a chroma will produce little to no improvements

Reverse test:
SAMPLE CLIP: 8 loops of a short video
TEST1: no reversing (2:35)
TEST2: alternately reversing (12:33)
CONCLUSION: reversing clips will SIGNIFICANTLY INCREASE render time (up to 600%)