save file as png with lower bit depths in matlab

To save an image as PNG with lower bit depths in MATLAB, you can use the imwrite function. The imwrite function can take the following syntax:

main.m
imwrite(A, filename, 'png', 'BitDepth', bitdepth);
51 chars
2 lines

where:

• A is the image matrix to be saved
• filename is the name of the PNG file to be saved
• 'png' specifies the file format
• 'BitDepth' specifies the desired bit depth of the saved image (8, 4 or 2 bit)
• bitdepth is an integer value indicating the bit depth.

Here's an example of how to save an image as PNG with 4-bit depth:

main.m
original_image = imread('example_image.bmp');
png_filename = 'example_image_4bit.png';
imwrite(original_image, png_filename, 'png', 'BitDepth', 4);
148 chars
4 lines

This will save the original_image as a PNG file with 4-bit depth and the file will be named example_image_4bit.png.