Thread: Reading 1D data into 2D array

For my video processing program, I'm attempting to merge a series of video frames to get a sensation of a higher frame rate but be played back at a higher speed. Merging 5 frames together (5 BMP files) for example, has 5 frames merged together, appears to play at 150 fps but plays back at 30 fps giving the sense of 5x time. What my question is involves reading and writing multidimensional arrays, 2D arrays in my case. How would I do so in my read/write functions and set it up otherwise?

Code:

... // includes, defines and globals
unsigned char FrameData[1036800][5]; // 5 frames' worth of 720x480x24 images

... // other globals and function to get file path and names

fread(&FrameData[0], 1, 1036800, FileHandle); // read 1,036,800 bytes of dataj // ???

... // Brighten, merge, then crop - these functions (except the newest merge) all work as expected but need adjusting

fwrite(&OutputFrameData, 1, CroppedImageDataSize, FileHandle); // write related single frame

... // main function

The two questions/concerns are:

1. For the variable declaration, what should the order of the elements be? In other words, should the big number be first or second?
2. Since I want to read the data into the large part of the array, how would I do so?

The reason is for a loop to process the input frames making it easier to do (otherwise, it'd just be a big mess with many very similar instructions.

> 1. For the variable declaration, what should the order of the elements be?
Consider
char lines[LINES_PER_FILE][CHARS_PER_LINE];
as a template for your ideas.

So the smaller number should be first in my case or:

Code:

unsigned char FrameData[FrameCount][BytesPerFrame];

Then, what about the second question/concern where I read into the array? How would I read into the large dimension of it rather than the smaller (since that would cause array overflow). Each original BMP file is always the same size - 720x480 at 24-bit color meaning 1,036,800 bytes are needed (just shy of 1 MB).

I guess
for ( frameNum = 0 ; frameNum < 5 ; frameNum++ ) fread( FrameData[frameNum], 1, 1036800, FileHandle);

I got it working now and fixed unrelated bugs. It goes like this:

Code:

unsigned char Data[NumberOfFrames][FrameData];

...

fread(Data[FrameNumber], 1, Size, FileHandle);

The results I got were a bit unexpected at first, but I've got everything working now and I'll be posting this video on YouTube when I finish processing it. Thanks.