![background image](http://html1.mh-extra.com/html/texas-instruments/dm38x-davinci/dm38x-davinci_user-manual_1097067180.webp)
Internal Modules
180
SPRUHI7A – December 2012 – Revised June 2016
Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
Temporal interpolation can be disabled by programmable control registers. In that case we have:
ŷ
(j, i, n) = y
spat
(j, i, n)
Chroma interpolation is handled in the same manner as luma with regards to the above equations. There
is a separate control for disabling temporal interpolation for chroma, such that luma can perform the full
mixture, and chroma can only be spatial. If luma temporal interpolation is disabled, chroma temporal
interpolation is also disabled.
The
provides a simple description of how a motion-adaptive deinterlacer operates. The
actual interpolation used is edge directed interpolation. Edge directed interpolation is only performed
spatially prior to the output mixing.
1.2.9.2.1 Modes of Operation
The DEI can be operated in bypass mode and deinterlacer mode.
1.2.9.2.1.1 Bypass Mode
In the bypass mode, input luma and chroma are buffered and sent to the stage after DEI without
processing.
To set DEI in the bypass mode, the bypass bit must be set accordingly in the configuration register.
1.2.9.2.1.2 Film Mode Detection (FMD)
Film mode detection is performed by both hardware and software. In every field, the hardware
accumulates difference between two neighboring frames (two top fields or two bottom fields), difference
between two adjacent fields, and combing artifact. At the end of DEI data processing, an interrupt will be
sent to the processor. The processor needs to read three status registers from DEI, calculate whether the
film mode has been entered or existed, and update film mode lock and jam direction (fmd_cfg0) MMR of
DEI before the next field starts. Since it is a time sensitive processing, the FMD interrupt has to be a high
priority interrupt to the processor.
Film mode detection can be performed on a full picture size or a smaller window specified by a few MMR
registers. The interrupt is always asserted at the end of the entire DEI data processing and is not affected
by the window size and location.
Implementing film mode detection algorithm in software allows more flexibility at the cost of timing critical
interface between DEI and the processor. For example, customers may find later that supporting 3-2-2-3
pull down is needed. This feature can be easily added by upgrading only the FMD software.
FMD feature is supported by the DEI module. More details about FMD mode, they are discussed in the
DEI_H section.
See the appendix for configuration details on FMD.
1.2.9.2.1.3 Deinterlacer Mode
In the deinterlacer mode, DEI takes in alternative field YUV data and sends out a sequential frame YUV
data by interpolation techniques mentioned below.
DEI supports four interpolation modes when converting interlaced pictures to progressive pictures.