How to turn matrix of floats to unsigned bytes?

[yamahabob]

I have a matrix of float values that I need to make a PGM file out of. I think I need to turn these into an array of unsigned chars (correct me if I'm wrong). I need to know how to go about doing this.

I have read about fcvt, but I'm not sure if this is what I need since it splits things into separate parts. Any help is greatly appreciated.

Thanks in advance

[CommonTater]

Take a look at what fprintf() can do. I think you'll find it adequate to the task.

[quzah]

What is is you're actually trying to do? Store the value of the float in the range allowed for an unsigned char, or write the float out in binary to file?


Quzah.

[CommonTater]

What is is you're actually trying to do? Store the value of the float in the range allowed for an unsigned char, or write the float out in binary to file?


Quzah.

Hmmmm... good point.... I took it as the latter.

[itCbitC]

Walk along the float matrix using a char* and store the de-referenced value in a char[].

[yamahabob]

What is is you're actually trying to do? Store the value of the float in the range allowed for an unsigned char, or write the float out in binary to file?


Quzah.

The first. I have been trying to remove rings from images created during a neural scan. I end up manipulating arrays of floats. Now that I'm done, I need to write out a matrix of unsigned bytes.

Walk along the float matrix using a char* and store the de-referenced value in a char[].

This sort of sounds like it might be what I need. Is there a way to going float by float and convert it to unsigned chars along the way?

[GReaper]

Multiply each float by 255 and store the result in the output file as a char.

To do the above without losing *much* information, your float must be in the range [0.0f, 1.0f]

[yamahabob]

Multiply each float by 255 and store the result in the output file as a char.

To do the above without losing *much* information, your float must be in the range [0.0f, 1.0f]

Store each one as a char* ?

[laserlight]

Now that I'm done, I need to write out a matrix of unsigned bytes.

What are you going to do with that matrix of unsigned char?

[GReaper]

Store each one as a char* ?

As a char.

[yamahabob]

What are you going to do with that matrix of unsigned char?

Adding the proper header, this can be viewed as a PGM image.

[yamahabob]

As a char.

This seems to be working! Thanks for the help