We are working with the ADV7280 and have this decoder on a PCB and connected to NTSC camera.
The problem we are trying to solve is we want to get both even and odd fields in a non-progressive mode into a single frame, one field followed by the other. This way we get all of the image information in a single frame and we can de-interlace the image in our software. We do not want the decoder to convert the image to a progressive scan image because this conversion is done by interpolating every other line, not by using actual image data.
Here are the setting we are using:
Keep in mind that these setting are for progressive mode. We want to change these to interlaced and display both fields in a single frame.
<!-- Configure ADV 7280 Analog to Digital Decoder -->
<!-- :Autodetect CVBS Single Ended In Ain 1, Parallel output BT656: -->
<Write Adapter="Service" SlaveID="40" Register="0F" Value="40" /> <!-- System Reset -->
<Delay Duration_ms="10" />
<Write Adapter="Service" SlaveID="40" Register="0F" Value="00" /> <!-- System out of powerdown mode -->
<Write Adapter="Service" SlaveID="40" Register="00" Value="00" /> <!-- CVBS input on AIN1 -->
<Write Adapter="Service" SlaveID="40" Register="02" Value="04" /> <!-- Autodetect PAL B, PAL G, PAL H, PAL I, PAL D, NTSC J, SECAM -->
<Write Adapter="Service" SlaveID="40" Register="0E" Value="80" />
<Write Adapter="Service" SlaveID="40" Register="9C" Value="00" />
<Write Adapter="Service" SlaveID="40" Register="9C" Value="FF" />
<Write Adapter="Service" SlaveID="40" Register="0E" Value="00" /> <!-- Enter user sub-map -->
<Write Adapter="Service" SlaveID="40" Register="03" Value="0C" /> <!-- Output signal drivers are enabled -->
<Write Adapter="Service" SlaveID="40" Register="6A" Value="10" /> <!-- HS pin outputs horizontal sync signal -->
<Write Adapter="Service" SlaveID="40" Register="32" Value="41" /> <!-- //C1 -->
<Write Adapter="Service" SlaveID="40" Register="6B" Value="11" /> <!-- VS pin outputs vertical sync signal, 0x11=VSYNC, 0x12=Field -->
<Write Adapter="Service" SlaveID="40" Register="04" Value="3C" /> <!-- Output format ITU-R BT.656-3 use 0x3C; BT.656-4 use 0xBC-->
<Write Adapter="Service" SlaveID="40" Register="13" Value="00" /> <!-- Detect 60Hz video -->
<Write Adapter="Service" SlaveID="40" Register="15" Value="00" /> <!-- Digital clamp (dc bias restore) response TC set to fast 0.1s -->
<Write Adapter="Service" SlaveID="40" Register="17" Value="41" /> <!-- Select SH1 input filter -->
<Write Adapter="Service" SlaveID="40" Register="1D" Value="40" /> <!-- Enable pixel clock -->
<Write Adapter="Service" SlaveID="40" Register="37" Value="01" /> <!-- Pixel clock polarity not reversed -->
<Write Adapter="Service" SlaveID="40" Register="F4" Value="3F" /> <!-- IO Drive Strength (High Drive Strength) -->
<Write Adapter="Service" SlaveID="40" Register="52" Value="CD" />
<Write Adapter="Service" SlaveID="40" Register="80" Value="51" />
<Write Adapter="Service" SlaveID="40" Register="81" Value="51" />
<Write Adapter="Service" SlaveID="40" Register="82" Value="68" />
<!-- Enable de-interlacer -->
<Write Adapter="Service" SlaveID="40" Register="FD" Value="84" />
<Write Adapter="Service" SlaveID="84" Register="A3" Value="00" /> <!-- ADI Required Write [ADV7280 VPP writes begin] -->
<Write Adapter="Service" SlaveID="84" Register="5B" Value="00" /> <!-- Enable Advanced Timing Mode -->
<Write Adapter="Service" SlaveID="84" Register="55" Value="80" /> <!-- //0x80 = Interlaced to Progressive ON; 0x00 = interlaced-->
Attached are images we acquired for Progressive mode and for field sync interlaced mode (odd or even).
For progressive:
The image is interpolated by the decoder to add the missing lines on each frame received for even (one frame) and for odd (the next frame).
See Progressive.PNG attached.
Interlaced single field (odd or even):
The interlaced image is only one field, either the even or the odd field. We would like to get both fields in a single image.
See Interlaced single field.PNG attached.
