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Altera_Forum
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15 years ago

Scaler II vs Scaler problems

Hi, I have a working video processing design that includes the Scaler (v 9.1sp2). In the design I need to convert from 4:2:2 to 4:4:4, scale the video, and then go back to 4:2:2. With the Sc...
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Altera_Forum
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15 years ago

Hi Kieron,

Thanks for the thorough explanation of the blanking option! Some clarification in the documentation would indeed be welcome. I have still not been able to solve my problem. My datapath is as follows:

CVI -> DeInterlacer(MA) -> CRS -> Scaler -> CRS -> VideoOut

(The system is much more complex, but I have taken out all the non-essential blocks to debug this). VideoOut is a custom IP block that does the same as CVO, but includes a tripple frame FIFO buffer and a few other enhancements I required.

The above data path works fine with the original scaler. I have tried two versions with the Scaler II:

CVI -> DI -> Scaler II (422 mode) -> VideoOut

and

CVI -> DI -> CRS -> Scaler II (444 mode) -> CRS -> VideoOut

In both cases I get CVI FIFO overflows and almost no video output. I have set the options of the Scaler II to exactly the same options as I have for the Scaler. The options are as follows:

Bits per symbol: 8

Symbols in parallel: 2/3

Symbols in sequnece: 1

Enable Run Time control of input/output frame size

Maximum Input Frame Width: 1920

Maximum Input Frame Height: 1080

Maximum Output Frame width: 1920

Maximum Output Frame Height: 1080

4:2:2 data (in one case selected, in the other not)

Algorithm: Bilinear

I have not added any extra pipelining registers.

I need the 1920x1080 in the final system, but for testing now the input stream is 576p50 and the output is set to 1280 x 720. I can also set the output to 720 x 576 (in other words - no scaling required) and in both cases I get the same problem with Scaler II. The original scaler works 100% in all cases.

The only non-Altera block in this chain is my custom VideoOut block, but the system has been working flawlessly for a while now using the original scaler, so I have a fair amount of confidence in my custom VideoOut block. Also, I can put in a mode where it ignores all incoming data and applies no backpressure (it always asserts ready) and even then I see the CVI FIFO overflow.

My next step will be to bring out the ST input and output interface flow control signals of the Scaler to debug pins so that I can see what is going on.

BTW, I have Quartus 10.1, build 197 with SP1 (Full Version).

Regards,

Niki