MP4 messes up the brightness

[midnait]

i've been noticing that videos encoded with mp4 in Sony Vegas turn out to get a slight underexposed burn

i can compensate for this by adjusting the brightness and contrast of the project, before i render...but no matter what i do, the white level of the final render is always reduced to a smoky gray

the same thing seems to be the case when i encode to wmv as well...while on the contrary of mp4, the contrast appears to be slightly reduced

is there any way i can prevent the codec from tweaking the brightness and contrast?

[poisondeathray]

Unlikely to be fault of the container or codec. More likely a workflow error or playback rendering issue.

What is your source format and describe your workflow? Vegas handles different source formats differently in regards to levels and colorspace. If it's something like FRAPS, it would likely be full RGB (0-255). If you don't setup the vegas setting correctly, it will clip the levels

How are you determining this? Are you sure it's not a playback issue with renderer choice (e.g. vrm9 renderless vs. overlay)?

Some good info in these links below. Basically I do what edDV suggests; make a video with same specs as your input from a testchart and run it through the workflow to find out what you are doing wrong.

https://forum.videohelp.com/topic352511.html
http://www.glennchan.info/articles/vegas/v8color/v8color.htm

[midnait]

i don't know much about the technical aspects of video processing, so i'm not quite sure what you're leading in to

i determined the result by eye from playback in Media Player Classic, and by loading the rendered clip into Vegas again to compare with the original

the image below illustrates the difference between the original clip (above) and the rendered



they're both snapshots exported from Vegas

[poisondeathray]

Again, what is your source format? where did you get it from? use mediainfo if you don't know

Try 32-bit project settings in vegas. It could be a levels issues (studio vs. computer RGB) as alluded to above. Do a quick test render on a small section, it should only take a few seconds to test this.

[midnait]

thanks, i finally figured it out

it was indeed the pixel format of the project settings

i changed it from 8-bit to 32-bit and rendered...perfect!