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I have seen several reports of people having problems with high resolution displays, commonly on 1080p displays. But, I could never reproduce it on my systems. I recently got access to a new iMac with a 1920x1200 display and was able to see the problem, and I wanted to see if anyone else has done any debugging on this. <div><br class="webkit-block-placeholder"></div><div>I'll include a lot of details below.. the executive summary is:</div><div> - Choppy playback of 1080i video with Mac front-end on 1080P+ displays.</div><div> - When the problem is seen, Scaling + color conversion takes a large percentage of CPU, but function is absent in normal playback scenarios.</div><div> - Quicktime may be kicking scaling to a software function rather than normal hardware scaling/color conversion, when this issue is seen.</div><div><br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div>Problem details: Mac OS X front-end, "Scale Video as Needed" turned ON in setup,1080i video. Playback of video generates a very high CPU load, and the video is very choppy as if it is skipping many frames. This is seen on several versions, including 0.20.2 and 0.21svn.</div><div><br></div><div>I used Apple's Shark profiling tool to see where the CPU was being used when the problem was happening. The top users were:</div><div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">41.7% YUV422_UC_ToRGB32BitColorBGRA</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">7.7% ml_set_interrupts_enabled</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">7.0% mmx_i420_2vuy</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">6.0% mpeg_decode_mb</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">4.7% linearBlendMMX </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Obviously, YUV422_UC_ToRGB32BitColorBGRA is the big consumer here. The chain of function calls leading to YUV422 looks like:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">VideoOutputQuartzView::Show()</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">DecompressSequenceFrameWhen</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">.... (snipped) ...</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">YUV422CodecComponentDispatch</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">ScalingCodecComponentDispatch</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">... (snip) ...</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">PrepareForBlitThenDoBlit</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">FinalGlueBeforeTheBlit</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">YUV422_UC_ToRGB32BitColorBGRA</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Turning off "Scale video as necessary" causes YUV422_UC_ToRGB32BitColorBGRA to be removed from the CPU user list completely. </div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Also, if I run MythFrontend on my MacBook Pro, where the problem doesn't happen, I don't see YUV422_UC_ToRGB32BitColorBGRA whether scaling is on or off.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Some other threads mentioned modifying videoout_quartz.cpp to modify the video / aspect-ratio detection, so I tried that. The code changed was:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> DeleteQuartzBuffers();</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> </font><br class="khtml-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> data->srcWidth = input_size.width();</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> data->srcHeight = input_size.height();</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> data->srcAspect = aspect;</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> data->srcMode = db_aspectoverride;</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> </font><br class="khtml-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">+ if ( data->srcWidth == 1920 && data->srcHeight == 1088 )</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">+ data->srcHeight = 1080;</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> </font><br class="khtml-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica"> CreateQuartzBuffers(); </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Once I changed that, the first few programs I tried played back flawlessly, and YUV422_UC_ToRGB32BitColorBGRA was no longer in the list in Shark. But, in further testing with an 0.20.2 front-end, the problem still showed up with some 1080i programs. (In my 0.21svn version the few programs I tried worked fine. But, that was a test back-end, so I had few programs to try it with. I modified the 0.20.2 front-end and tried with my more plentiful program list on that back-end, and found that many 1080i programs still showed the problem, by several worked fine with the hack in place.)</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">CPU Usage in good video playback (lower resolution displays, with scaling turned off, or on some programs with the hack in place) looks like:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">22.2% mach_kernel ml_set_interrupts_enabled</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">9.7% mythavcodec mpeg_decode_mb</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">8.7% commpage __longcopy</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">8.6% mythtv mmx_yuv420_2vuy</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">5.5% mythavcodec ff_simple_idct_add_mmx</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: 12.0px Helvetica">..... </font></div> </div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">So, my guess is that there is an issue in some 1080i programs, or the QuickTime library usage, that causes the scaling and color conversion to be kicked to a software function. But, I know nothing about QuickTime, so that's just a guess.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Anyone else got any debugging info about this, or QuickTime experience with similar issues?</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Also note: Some previous reports of this problem on a Mac Mini thought it was because the Mini or the Mini's integrated GPU was not powerful enough. Most of my testing was on a new iMac (2.4GHz Core2Duo, 2GB RAM, ATI GPU). So, the issue is not just a power limit.</div></div> </div> </div> </div></body></html>