Delphi-OpenCV/source/ffmpeg/ffm.pixdesc.pas

(*
  * pixel format descriptor
  * Copyright (c) 2009 Michael Niedermayer <michaelni@gmx.at>
  *
  * This file is part of ffm.
  *
  * 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
*)

unit ffm.pixdesc;

{$i ffmpeg.inc}

interface

uses
  ffm.pixfmt;

Type

  pAVComponentDescriptor = ^TAVComponentDescriptor;

  TAVComponentDescriptor = {packed} record
    // uint16_t plane        :2;            ///< which of the 4 planes contains the component
    (*
      * Number of elements between 2 horizontally consecutive pixels minus 1.
      * Elements are bits for bitstream formats, bytes otherwise.
    *)
    // uint16_t step_minus1  :3;
    (*
      * Number of elements before the component of the first pixel plus 1.
      * Elements are bits for bitstream formats, bytes otherwise.
    *)
    // uint16_t offset_plus1 :3;
    // uint16_t shift        :3;            ///< number of least significant bits that must be shifted away to get the value
    // uint16_t depth_minus1 :4;            ///< number of bits in the component minus 1
    data: uint16;
  end;

  (*
    * Descriptor that unambiguously describes how the bits of a pixel are
    * stored in the up to 4 data planes of an image. It also stores the
    * subsampling factors and number of components.
    *
    * @note This is separate of the colorspace (RGB, YCbCr, YPbPr, JPEG-style YUV
    *       and all the YUV variants) AVPixFmtDescriptor just stores how values
    *       are stored not what these values represent.
  *)
  pAVPixFmtDescriptor = ^TAVPixFmtDescriptor;

  TAVPixFmtDescriptor = {packed} record
    name: pAnsiChar;
    nb_components: uint8;
    /// < The number of components each pixel has, (1-4)
    (*
      * Amount to shift the luma width right to find the chroma width.
      * For YV12 this is 1 for example.
      * chroma_width = -((-luma_width) >> log2_chroma_w)
      * The note above is needed to ensure rounding up.
      * This value only refers to the chroma components.
    *)
    log2_chroma_w: uint8;
    /// < chroma_width = -((-luma_width )>>log2_chroma_w)
    (*
      * Amount to shift the luma height right to find the chroma height.
      * For YV12 this is 1 for example.
      * chroma_height= -((-luma_height) >> log2_chroma_h)
      * The note above is needed to ensure rounding up.
      * This value only refers to the chroma components.
    *)
    log2_chroma_h: uint8;
    flags: uint8;
    (*
      * Parameters that describe how pixels are {packed}.
      * If the format has 2 or 4 components, then alpha is last.
      * If the format has 1 or 2 components, then luma is 0.
      * If the format has 3 or 4 components,
      * if the RGB flag is set then 0 is red, 1 is green and 2 is blue;
      * otherwise 0 is luma, 1 is chroma-U and 2 is chroma-V.
    *)
    comp: array [0 .. 3] of TAVComponentDescriptor;
  end;

const
  (*
    * Pixel format is big-endian.
  *)
  AV_PIX_FMT_FLAG_BE = (1 shl 0);
  (*
    * Pixel format has a palette in data[1], values are indexes in this palette.
  *)
  AV_PIX_FMT_FLAG_PAL = (1 shl 1);
  (*
    * All values of a component are bit-wise {packed} end to end.
  *)
  AV_PIX_FMT_FLAG_BITSTREAM = (1 shl 2);
  (*
    * Pixel format is an HW accelerated format.
  *)
  AV_PIX_FMT_FLAG_HWACCEL = (1 shl 3);
  (*
    * At least one pixel component is not in the first data plane.
  *)
  AV_PIX_FMT_FLAG_PLANAR = (1 shl 4);
  (*
    * The pixel format contains RGB-like data (as opposed to YUV/grayscale).
  *)
  AV_PIX_FMT_FLAG_RGB = (1 shl 5);
  (*
    * The pixel format is "pseudo-paletted". This means that FFmpeg treats it as
    * paletted internally, but the palette is generated by the decoder and is not
    * stored in the file.
  *)
  AV_PIX_FMT_FLAG_PSEUDOPAL = (1 shl 6);
  (*
    * The pixel format has an alpha channel.
  *)
  AV_PIX_FMT_FLAG_ALPHA = (1 shl 7);

{$IFDEF FF_API_PIX_FMT}
  (*
    * @deprecated use the AV_PIX_FMT_FLAG_* flags
  *)
  PIX_FMT_BE = AV_PIX_FMT_FLAG_BE;
  PIX_FMT_PAL = AV_PIX_FMT_FLAG_PAL;
  PIX_FMT_BITSTREAM = AV_PIX_FMT_FLAG_BITSTREAM;
  PIX_FMT_HWACCEL = AV_PIX_FMT_FLAG_HWACCEL;
  PIX_FMT_PLANAR = AV_PIX_FMT_FLAG_PLANAR;
  PIX_FMT_RGB = AV_PIX_FMT_FLAG_RGB;
  PIX_FMT_PSEUDOPAL = AV_PIX_FMT_FLAG_PSEUDOPAL;
  PIX_FMT_ALPHA = AV_PIX_FMT_FLAG_ALPHA;
{$ENDIF}
{$IFDEF FF_API_PIX_FMT_DESC}
  (*
    * The array of all the pixel format descriptors.
  *)
extern attribute_deprecated

const
AVPixFmtDescriptor av_pix_fmt_descriptors[];
{$ENDIF}
(*
  * Read a line from an image, and write the values of the
  * pixel format component c to dst.
  *
  * @param data the array containing the pointers to the planes of the image
  * @param linesize the array containing the linesizes of the image
  * @param desc the pixel format descriptor for the image
  * @param x the horizontal coordinate of the first pixel to read
  * @param y the vertical coordinate of the first pixel to read
  * @param w the width of the line to read, that is the number of
  * values to write to dst
  * @param read_pal_component if not zero and the format is a paletted
  * format writes the values corresponding to the palette
  * component c in data[1] to dst, rather than the palette indexes in
  * data[0]. The behavior is undefined if the format is not paletted.
*)
// void av_read_image_line(uint16_t *dst, const uint8_t *data[4], const int linesize[4],
// const AVPixFmtDescriptor *desc, int x, int y, int c, int w, int read_pal_component);

(*
  * Write the values from src to the pixel format component c of an
  * image line.
  *
  * @param src array containing the values to write
  * @param data the array containing the pointers to the planes of the
  * image to write into. It is supposed to be zeroed.
  * @param linesize the array containing the linesizes of the image
  * @param desc the pixel format descriptor for the image
  * @param x the horizontal coordinate of the first pixel to write
  * @param y the vertical coordinate of the first pixel to write
  * @param w the width of the line to write, that is the number of
  * values to write to the image line
*)
// void av_write_image_line(const uint16_t *src, uint8_t *data[4], const int linesize[4],
// const AVPixFmtDescriptor *desc, int x, int y, int c, int w);

(*
  * Return the pixel format corresponding to name.
  *
  * If there is no pixel format with name name, then looks for a
  * pixel format with the name corresponding to the native endian
  * format of name.
  * For example in a little-endian system, first looks for "gray16",
  * then for "gray16le".
  *
  * Finally if no pixel format has been found, returns AV_PIX_FMT_NONE.
*)
// enum AVPixelFormat av_get_pix_fmt(const char *name);

(*
  * Return the short name for a pixel format, NULL in case pix_fmt is
  * unknown.
  *
  * @see av_get_pix_fmt(), av_get_pix_fmt_string()
*)
// const char *av_get_pix_fmt_name(enum AVPixelFormat pix_fmt);
function av_get_pix_fmt_name(pix_fmt: TAVPixelFormat): pAnsiChar; cdecl;

(*
  * Print in buf the string corresponding to the pixel format with
  * number pix_fmt, or a header if pix_fmt is negative.
  *
  * @param buf the buffer where to write the string
  * @param buf_size the size of buf
  * @param pix_fmt the number of the pixel format to print the
  * corresponding info string, or a negative value to print the
  * corresponding header.
*)
// char *av_get_pix_fmt_string (char *buf, int buf_size, enum AVPixelFormat pix_fmt);

(*
  * Return the number of bits per pixel used by the pixel format
  * described by pixdesc. Note that this is not the same as the number
  * of bits per sample.
  *
  * The returned number of bits refers to the number of bits actually
  * used for storing the pixel information, that is padding bits are
  * not counted.
*)
// int av_get_bits_per_pixel(const AVPixFmtDescriptor *pixdesc);

(*
  * Return the number of bits per pixel for the pixel format
  * described by pixdesc, including any padding or unused bits.
*)
// int av_get_padded_bits_per_pixel(const AVPixFmtDescriptor *pixdesc);

(*
  * @return a pixel format descriptor for provided pixel format or NULL if
  * this pixel format is unknown.
*)
// const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt);

(*
  * Iterate over all pixel format descriptors known to libavutil.
  *
  * @param prev previous descriptor. NULL to get the first descriptor.
  *
  * @return next descriptor or NULL after the last descriptor
*)
// const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev);

(*
  * @return an AVPixelFormat id described by desc, or AV_PIX_FMT_NONE if desc
  * is not a valid pointer to a pixel format descriptor.
*)
// enum AVPixelFormat av_pix_fmt_desc_get_id(const AVPixFmtDescriptor *desc);

(*
  * Utility function to access log2_chroma_w log2_chroma_h from
  * the pixel format AVPixFmtDescriptor.
  *
  * See avcodec_get_chroma_sub_sample() for a function that asserts a
  * valid pixel format instead of returning an error code.
  * Its recommanded that you use avcodec_get_chroma_sub_sample unless
  * you do check the return code!
  *
  * @param[in]  pix_fmt the pixel format
  * @param[out] h_shift store log2_chroma_w
  * @param[out] v_shift store log2_chroma_h
  *
  * @return 0 on success, AVERROR(ENOSYS) on invalid or unknown pixel format
*)
// int av_pix_fmt_get_chroma_sub_sample(enum AVPixelFormat pix_fmt,
// int *h_shift, int *v_shift);

(*
  * @return number of planes in pix_fmt, a negative AVERROR if pix_fmt is not a
  * valid pixel format.
*)
// int av_pix_fmt_count_planes(enum AVPixelFormat pix_fmt);

// void ff_check_pixfmt_descriptors(void);

(*
  * Utility function to swap the endianness of a pixel format.
  *
  * @param[in]  pix_fmt the pixel format
  *
  * @return pixel format with swapped endianness if it exists,
  * otherwise AV_PIX_FMT_NONE
*)
// enum AVPixelFormat av_pix_fmt_swap_endianness(enum AVPixelFormat pix_fmt);

implementation

uses ffm.lib;

function av_get_pix_fmt_name;external avutil_dll;

end.