Changing the Color of Pixels

[jhood135]

I'm incredibly new in the world of coding with Premiere, so my apologies if I'm not using the right terms...

I'm trying to write a plugin that will scan every pixel in a clip. I want it to act almost like a FCP Broadcast Safe filter, making the pixels that are too bright darker. I assumed that using an If-Else structure would be the best way to do this, however I don't know what to declare in the If statement. I'm using the Simple_Video_Filter example from the SDK package. Here's the section of the code I'm working on (again, apologies for how bad it is...)

                    for(int vert = 0; vert < height; ++vert)

                    {

                        for(int horiz = 0; horiz < width; ++horiz)

                        {

                            // Save off alpha

                            alpha = *srcpix & 0xff000000;

                            // Separate colors

                            redSource = (*srcpix & 0x00ff0000) >> 16;

                            greenSource = (*srcpix & 0x0000ff00) >> 8;

                            blueSource = *srcpix & 0x000000ff;

                            if (redSource == 0x00ff0000) {

                                redSource = *srcpix & 0x000000ff;

                                OutputDebugString(TEXT("Red detected."));

                            }

                            else {

                                OutputDebugString(TEXT("No Red."));

                            }

                            *dstpix = (alpha | (redSource << 16) | (greenSource << 8) | blueSource);

                            ++dstpix;

                            ++srcpix;

                        }

                        srcpix += (rowbytes / 4) - width;

                        dstpix += (rowbytes / 4) - width;

                    } // else

On a colour matte with the value of FF0000, it still prints out "No Red."

Can someone please advise, or at least point me in the right direction?

Thanks.

-Josh

[Eddie Lotter]

Change the line

if (redSource == 0x00ff0000) {

to

if (redSource == 0x000000ff) {

and you will see the test "Red detected" if any of the pixels contain full red.
However, what you do with it also seems suspect.

Cheers
Eddie

[Zac Lam · Accepted solution]

Eddie, long time, great to see you on the forums!

Josh, stepping back a little further, I wanted to point out that the Simple_Video_Filter uses a legacy API and because of that it's been removed from the BuildAll .sln / .xcodeproj in the latest SDK.  We recommend starting from a sample effect project in the After Effects SDK.  For example the Portable sample is good if you just want 8-bit RGB.  Or the SDK_Noise sample if you want to support 32-bit float and even YUV-native processing.

[Eddie Lotter]

Eddie, long time, great to see you on the forums!

Hey Zac.

Yes, I'm still rattling around here.

Cheers

Eddie