fast 0..255 * 0..255 => 0..255 rounded multiplication

if there's a pending marker from the entropy stream, return that otherwise, fetch from the stream and get a marker. if there's no marker, return 0xff,

take a -128..127 value and stbi__clamp it and convert to 0..255

returns 1 if "a*b*c + add" has no negative terms/factors and doesn't overflow

initialize a callback-based context

initialize a memory-decode context

returns 1 if the product is valid, 0 on overflow. negative factors are considered invalid.

clean up the temporary component buffers

decode a jpeg huffman value from the bitstream

after a restart interval, stbi__jpeg_reset the entropy decoder and the dc prediction

mallocs with size overflow checking

combined JPEG 'receive' and JPEG 'extend', since baseline always extends everything it receives.

returns 0..31 for the highest set bit

extract an arbitrarily-aligned N-bit value (N=bits) from v, and then make it 8-bits long and fractionally extend it to full full range.

returns STBI_rgb or whatever, 0 on error

return 1 if the sum is valid, 0 on overflow. negative terms are considered invalid.

returns 1 if the sum of two signed ints is valid (between -2^31 and 2^31-1 inclusive), 0 on overflow.

adds an extra all-255 alpha channel dest == src is legal img_n must be 1 or 3

create the png data from post-deflated data

this function is designed to support animated gifs, although stb_image doesn't support it two back is the image from two frames ago, used for a very s

decode one 64-entry block--

get some unsigned bits