Originally Posted by MovieSwede /forum/post/0
Even the BBC has been up for discussion in another thread. And if you look closely you can se colorareas in the VC1 that the broadcast version dont have. That could very well mean that the broadcast smears the banding.
Unless we have acces to the source we cant prove it one way or the other. Ben has already proven in other threads that VC1 can handle banding very well in low bitrates, but it cant take away banding that is inhearent to the master. Unless you lowers the bitrate even more.
So if we look at the facts.
We have seen lowbitrate encodings that handle banding well.
We have seen lowbitrate encodings that handle banding bad.
So then we can conclude that lowbitrate isnt a factor on its own, that create banding.
The problem with those scene is that they move, color is moving and swifting, the Banding test that the AVSFORUM member did was on a none shifting color band, color didn't moves. On all the banding i saw, MPEG2 and VC1 it was all because the bitrate gone lower than 5mbits in a moving shifting color range.
I'am pretty sure if i color color Dark Blue to light blue and i move the color, from lighter blue to even lighter blue.. or from Blue to Gray/Dark Gray, at 5mbits AVC and VC1 would have band.
I did a lot of h264 Profile 1 (AVC) encode with my HDTV TS grab in the past (last year), i did them at 7mbits VRB, and every single time the encoder saw something like this it plonge to 4 mbits and it was banding frenzy. I tried to correct it , but it would have had to be manually calibrated and i didn't have the patience.
The only way to correct that is to tell the encode not to go lower than 12mbits for example, with peak at 25, but that way you're movie is bigger.
I mean, from memory, i only see banding in Planet Earth, Happy Feet, Ant Bully, Superman return and Ice Age 2 (bluray). All those suffer from really low bitrate for their codec (Ice age 2 goes to 14mbits, for mpeg2 it's weak).. all others title, this is a none issue.