profile must already have been inited with mode. It's ok to set some parameters of profile to done already.*/

read the information from the header and store it in the LodePNGInfo. return value is error*/

** Here is the fun part, the median-cut colormap generator. This is based ** on Paul Heckbert's paper, "Color Image Quantization for Frame Buffer *

* Error reporting. **/

* Destructor. **/

* Constructor. **/

* Read initializer. **/

* Validator. **/

* Chunk filter */

* Analyze the redundancy of bits inside the image. * The parameter reductions indicates the intended reductions. * The function returns the possible

* Analyze the usage of samples. * The output value usage_map[n] indicates whether the sample n * is used. The usage_map[] array must have 256 entrie

* Clears an image object. */

* PNG file copying */

* Copies a PNG file stream to another PNG file stream. */

* Creates an optimizer object. * This is designed to be thread-safe, but it currently is THREAD-UNSAFE. */

* Creates a transformer object. */

* Imports an image from an image file stream. * The image may be either in PNG format or in an external file format. * The function returns 0 on suc

* Attempts to reduce the imported image. */

* Attempts to set and/or reset image data objects within the imported image. */

* Destroys an optimizer object. */

* Destroys a transformer object. */

* Stops the encoder. */

* Encodes an image to a PNG file stream. */

* Iteration finalization */

* Chunk handler */

* Iteration initialization */

* Prepares an I/O environment for processing. */

* Creates an I/O environment object. */

* Destroys an I/O environment object. */

* Commits an I/O environment. */

* Retrieves the backup file name. */

* Retrieves the output file name. */

* Initializes an I/O environment object. */

* Unrolls an I/O environment. */

* Tests whether a character is in the alphanumeric [0-9A-Za-z] range. */

* Tests whether a character is in the numeric [0-9] range. */

* Tests whether a character is in the uppercase alphabetic [A-Z] range. */

* Iteration */

* Finds the object id that corresponds to the given object name. */

* Optimizes an image file. */

* Image file optimization */

* Parses an input string in the form "object=value" and retrieves * the object id and value string. */

* Erases the line in which encoding parameters were printed. */

* Prints the file size difference line. */

* Prints the file size line. */

* Prints, in a compact form, the ratio between two numbers. */

* Prints the IDAT size difference line. */

* Prints the IDAT size line. */

* Prints a line of information regarding the image format. */

* Prints the status report. */

* Reads an image from an image file stream. * Reduces the image if possible. */

* Change the size of the transparency buffer. * Changing info_ptr->num_trans directly, avoiding reallocation, should * have been sufficient, but can

* Reduce the image type to a lower bit depth and color type, * by removing redundant bits. * Possible reductions: 16bpp to 8bpp; RGB to gray; strip

* Reduce the image (bit depth + color type + palette) without * losing any information. The palette (if applicable) and the * image data must be pre

* Reduce the palette. (Only the fast method is implemented.) * The parameter reductions indicates the intended reductions. * The function returns th

* Reduce the image type from grayscale(+alpha) or RGB(+alpha) to palette, * if possible. * The parameter reductions indicates the intended reduction

* Seals a transformer object. */

* Sets the transformer in an optimizer object. */

* Converts a chunk name to a chunk signature and adds it to * a chunk signature set. */

* Reads an object name from the given string. * A valid object has the form "[:alpha:]+(.[:alpha:]+)*". */

* Stores an image object into libpng structures. */

* Converts a numeric string representing a number to a smallint value. */

* Applies all set/reset transformations to the given libpng image structures. */

* Invalidate the unsafe-to-copy metadata that cannot reliably remain * after transformations. */

* Retrieves the precision values to be set for each channel. */

* Specifies a list of objects to be reset by the given transformer. */

* Sets the precision of the RGB (or gray) channels to a given value. * Returns 1 if this operation is applied, or 0 otherwise. */

* Copies the attributes (access mode, time stamp, etc.) of the source * file path onto the destination file path. */

* Creates a new directory. */

* Writes a block of data at the specified file offset. */

* Extracts the extension component of a path name. */

* Determines if a path is an accessible directory. */

* Determines if two accessible paths are equivalent. */

* N = automatic quality, uses limit unless force is set (N-N or 0-N) * -N = no better than N (same as 0-N) * N-M = no worse than N, no better tha