text: /*
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  #ifndef AVUTIL_IMGUTILS_H
  #define AVUTIL_IMGUTILS_H
  
  /**
   * @file
   * misc image utilities
   *
   * @addtogroup lavu_picture
   * @{
   */
  
  #include "avutil.h"
  #include "pixdesc.h"
  #include "rational.h"
  
  /**
   * Compute the max pixel step for each plane of an image with a
   * format described by pixdesc.
   *
   * The pixel step is the distance in bytes between the first byte of
   * the group of bytes which describe a pixel component and the first
   * byte of the successive group in the same plane for the same
   * component.
   *
   * @param max_pixsteps an array which is filled with the max pixel step
   * for each plane. Since a plane may contain different pixel
   * components, the computed max_pixsteps[plane] is relative to the
   * component in the plane with the max pixel step.
   * @param max_pixstep_comps an array which is filled with the component
   * for each plane which has the max pixel step. May be NULL.
   */
  void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
                                  const AVPixFmtDescriptor *pixdesc);
  
  /**
   * Compute the size of an image line with format pix_fmt and width
   * width for the plane plane.
   *
   * @return the computed size in bytes
   */
  int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane);
  
  /**
   * Fill plane linesizes for an image with pixel format pix_fmt and
   * width width.
   *
   * @param linesizes array to be filled with the linesize for each plane
   * @return >= 0 in case of success, a negative error code otherwise
   */
  int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width);
  
  /**
   * Fill plane data pointers for an image with pixel format pix_fmt and
   * height height.
   *
   * @param data pointers array to be filled with the pointer for each image plane
   * @param ptr the pointer to a buffer which will contain the image
   * @param linesizes the array containing the linesize for each
   * plane, should be filled by av_image_fill_linesizes()
   * @return the size in bytes required for the image buffer, a negative
   * error code in case of failure
   */
  int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int height,
                             uint8_t *ptr, const int linesizes[4]);
  
  /**
   * Allocate an image with size w and h and pixel format pix_fmt, and
   * fill pointers and linesizes accordingly.
   * The allocated image buffer has to be freed by using
   * av_freep(&pointers[0]).
   *
   * @param align the value to use for buffer size alignment
   * @return the size in bytes required for the image buffer, a negative
   * error code in case of failure
   */
  int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
                     int w, int h, enum AVPixelFormat pix_fmt, int align);
  
  /**
   * Copy image plane from src to dst.
   * That is, copy "height" number of lines of "bytewidth" bytes each.
   * The first byte of each successive line is separated by *_linesize
   * bytes.
   *
   * bytewidth must be contained by both absolute values of dst_linesize
   * and src_linesize, otherwise the function behavior is undefined.
   *
   * @param dst_linesize linesize for the image plane in dst
   * @param src_linesize linesize for the image plane in src
   */
  void av_image_copy_plane(uint8_t       *dst, int dst_linesize,
                           const uint8_t *src, int src_linesize,
                           int bytewidth, int height);
  
  /**
   * Copy image in src_data to dst_data.
   *
   * @param dst_linesizes linesizes for the image in dst_data
   * @param src_linesizes linesizes for the image in src_data
   */
  void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
                     const uint8_t *src_data[4], const int src_linesizes[4],
                     enum AVPixelFormat pix_fmt, int width, int height);
  
  /**
   * Setup the data pointers and linesizes based on the specified image
   * parameters and the provided array.
   *
   * The fields of the given image are filled in by using the src
   * address which points to the image data buffer. Depending on the
   * specified pixel format, one or multiple image data pointers and
   * line sizes will be set.  If a planar format is specified, several
   * pointers will be set pointing to the different picture planes and
   * the line sizes of the different planes will be stored in the
   * lines_sizes array. Call with src == NULL to get the required
   * size for the src buffer.
   *
   * To allocate the buffer and fill in the dst_data and dst_linesize in
   * one call, use av_image_alloc().
   *
   * @param dst_data      data pointers to be filled in
   * @param dst_linesizes linesizes for the image in dst_data to be filled in
   * @param src           buffer which will contain or contains the actual image data, can be NULL
   * @param pix_fmt       the pixel format of the image
   * @param width         the width of the image in pixels
   * @param height        the height of the image in pixels
   * @param align         the value used in src for linesize alignment
   * @return the size in bytes required for src, a negative error code
   * in case of failure
   */
  int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4],
                           const uint8_t *src,
                           enum AVPixelFormat pix_fmt, int width, int height, int align);
  
  /**
   * Return the size in bytes of the amount of data required to store an
   * image with the given parameters.
   *
   * @param[in] align the assumed linesize alignment
   */
  int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align);
  
  /**
   * Copy image data from an image into a buffer.
   *
   * av_image_get_buffer_size() can be used to compute the required size
   * for the buffer to fill.
   *
   * @param dst           a buffer into which picture data will be copied
   * @param dst_size      the size in bytes of dst
   * @param src_data      pointers containing the source image data
   * @param src_linesizes linesizes for the image in src_data
   * @param pix_fmt       the pixel format of the source image
   * @param width         the width of the source image in pixels
   * @param height        the height of the source image in pixels
   * @param align         the assumed linesize alignment for dst
   * @return the number of bytes written to dst, or a negative value
   * (error code) on error
   */
  int av_image_copy_to_buffer(uint8_t *dst, int dst_size,
                              const uint8_t * const src_data[4], const int src_linesize[4],
                              enum AVPixelFormat pix_fmt, int width, int height, int align);
  
  /**
   * Check if the given dimension of an image is valid, meaning that all
   * bytes of the image can be addressed with a signed int.
   *
   * @param w the width of the picture
   * @param h the height of the picture
   * @param log_offset the offset to sum to the log level for logging with log_ctx
   * @param log_ctx the parent logging context, it may be NULL
   * @return >= 0 if valid, a negative error code otherwise
   */
  int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx);
  
  /**
   * Check if the given sample aspect ratio of an image is valid.
   *
   * It is considered invalid if the denominator is 0 or if applying the ratio
   * to the image size would make the smaller dimension less than 1. If the
   * sar numerator is 0, it is considered unknown and will return as valid.
   *
   * @param w width of the image
   * @param h height of the image
   * @param sar sample aspect ratio of the image
   * @return 0 if valid, a negative AVERROR code otherwise
   */
  int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar);
  
  /**
   * @}
   */
  
  
  #endif /* AVUTIL_IMGUTILS_H */
  