Nvidia Quadro FX 4800 - Page 80

NVIDIA Corporation
76 Quadro FX 4800/5800 and Quadro CX SDI User’s Guide– Version 1.0
C
HAPTER 5
API Control
FRAMELOCK).
IfyouspecifyGENLOCKorFRAMELOCK,youshouldalsospecify
NV_CTRL_GVO_SYNC_SOU RCE.
• UseNV_CTRL_GVO_SYNC_INPUT_DETECTEDand
NV_CTRL_GVO_SDI_SYNC _INPU T_DETECTED todetectwhatinputsyncsare
present.
Ifnoanalogsyncisdetectedbutitisknownthatavalidbi‐levelortri‐levelsyncis
connected,setNV_CTRL_GVO_COMPOSITE_SYNC_INPUT_DETECT_MODE
appropriatelyandretestwith
NV_CTRL_GVO_COMPOSITE_ SYNC_INPUT_DETECTED
.
• Ifsyncingtoinputsync,querytheNV_CTRL_GVO_INPUT_VIDEO_FORMAT
attribute.
TheinputvideoformatcanonlybequeriedafterSYNC_SOURCEisspecified.
• SpecifytheNV_CTRL_GVO_OUTPUT_VIDEO_FORMAT.
• SpecifytheNV_CTRL_GVO_DATA_FORMAT.
• SpecifyanycustomColorSpaceConversion(CSC)matrix,offset,andscalewith
XNVCTRLSetGvoColorConversion().
• IfusingtheGLX_NV_video_outextensiontodisplayoneor
morepbuffers,call
glXGetVideoDeviceNV()tolocktheGVOoutputforusebytheGLXclient,then
bindthepbuffer(s)totheGVOoutputwithglXBindVideoImageNV()andsend
pbufferstotheGVOoutputwithglXSendPbufferToVideoNV().
SeetheGLX_NV_video_outspecformoredetails.
• If,ratherthanusingtheGLX _NV_video_outextensiontodisplayGLX
pbufferson
theGVOoutput,youwishdisplaytheXscreenontheGVOoutput,set
NV_CTRL_GVO_DISPLAY_X_SCREENto
NV_CTRL_GVO_DISPLAY_X_SCREEN_ENABLE.
• SettingmostGVOattributesonlycausesthevaluetobecachedintheXserver.
Thevalueswillbeflushedtothehardwareeitherwhen
NV_CTRL_GVO_DISPLAY_X_SCREENisenabled,orwhen
aGLXpbufferisboundto
theGVOoutput(withglXBindVideoImageNV()).
• GLX_NV_video_outandNV_CTRL_GVO_DISPLAY_X_SCREENaremutually
exclusive.
IfNV_CTRL_GVO_DISPLAY_X_SCREENisenabled,thenglXGetVideoDeviceNVwill
fail.Similarly,ifaGLXclienthaslockedtheGVOoutput(viaglXGetVideoDeviceNV),
thenNV_CTRL_GVO_DISPLAY_X_SCREENwillfail.The
NV_CTRL_GVO_GLX_LOCKEDeventwillbesentwhenaGLXclient
lockstheGVO
output.