Stereodude
15th January 2014, 21:43
Has anyone else noticed that the Intel HD Graphics 4600 have banding and posterization in the output when converting color spaces via EVR?
I have an old Dell FP2001 connected via DVI to the HD4600 graphics in a i7-4770k running Windows 7 SP1 that I use for video processing/compression. I spent a lot of time getting upset at why I couldn't get smooth color gradients (in real video content) from x264 when checking the output no matter what encoder settings I used (even lossless) when the Lagarith compressed intermediate AVI files looked flawless. I've been using MPC-HC 1.71 (32-bit and 64-bit) with the EVR (custom presenter) to play back the files for quality checking. There was obvious banding and posterization when I played back the x264 encoded files. After screwing around with x264 settings, debanding, adding grain, and other stuff in AVIsynth for about a week without being able to eliminate the banding I eventually discovered that the problem had nothing to do with x264, and everything to do with Intel's drivers. I had been using the initial release Haswell HD4600 drivers (05/17/2013 - 9.18.10.3186 / 15.31.11.64.3186). They ended up driving me nuts. I downloaded and installed the latest drivers (11/27/2013 -10.18.10.3345 / 15.33.8.64.3345) and they are better, but still have some less obvious banding / posterization and definitely aren't perfect. They aren't nearly as good as MadVR which looks flawless on the same gradients (using the same monitor and the HD4600's output), or another PC I have (Nvidia GTX 650 under XP) which also produces flawless looking gradients during playback.
FWIW, the banding/posterization in the output is there on both limited and full video level setting in the Intel driver control panel. Changing that setting has no impact on the gradients.
I plan to check the HD4400 in a Haswell i5-4300U for the same issue later tonight on my laptop.
I have an old Dell FP2001 connected via DVI to the HD4600 graphics in a i7-4770k running Windows 7 SP1 that I use for video processing/compression. I spent a lot of time getting upset at why I couldn't get smooth color gradients (in real video content) from x264 when checking the output no matter what encoder settings I used (even lossless) when the Lagarith compressed intermediate AVI files looked flawless. I've been using MPC-HC 1.71 (32-bit and 64-bit) with the EVR (custom presenter) to play back the files for quality checking. There was obvious banding and posterization when I played back the x264 encoded files. After screwing around with x264 settings, debanding, adding grain, and other stuff in AVIsynth for about a week without being able to eliminate the banding I eventually discovered that the problem had nothing to do with x264, and everything to do with Intel's drivers. I had been using the initial release Haswell HD4600 drivers (05/17/2013 - 9.18.10.3186 / 15.31.11.64.3186). They ended up driving me nuts. I downloaded and installed the latest drivers (11/27/2013 -10.18.10.3345 / 15.33.8.64.3345) and they are better, but still have some less obvious banding / posterization and definitely aren't perfect. They aren't nearly as good as MadVR which looks flawless on the same gradients (using the same monitor and the HD4600's output), or another PC I have (Nvidia GTX 650 under XP) which also produces flawless looking gradients during playback.
FWIW, the banding/posterization in the output is there on both limited and full video level setting in the Intel driver control panel. Changing that setting has no impact on the gradients.
I plan to check the HD4400 in a Haswell i5-4300U for the same issue later tonight on my laptop.