text: /*
   * XWD image format
   *
   * Copyright (c) 2012 Paul B Mahol
   *
   * 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
   */
  
  #include "libavutil/imgutils.h"
  #include "avcodec.h"
  #include "bytestream.h"
  #include "internal.h"
  #include "xwd.h"
  
  static int xwd_decode_frame(AVCodecContext *avctx, void *data,
                              int *got_frame, AVPacket *avpkt)
  {
      AVFrame *p = data;
      const uint8_t *buf = avpkt->data;
      int i, ret, buf_size = avpkt->size;
      uint32_t version, header_size, vclass, ncolors;
      uint32_t xoffset, be, bpp, lsize, rsize;
      uint32_t pixformat, pixdepth, bunit, bitorder, bpad;
      uint32_t rgb[3];
      uint8_t *ptr;
      GetByteContext gb;
  
      if (buf_size < XWD_HEADER_SIZE)
          return AVERROR_INVALIDDATA;
  
      bytestream2_init(&gb, buf, buf_size);
      header_size = bytestream2_get_be32u(&gb);
  
      version = bytestream2_get_be32u(&gb);
      if (version != XWD_VERSION) {
          av_log(avctx, AV_LOG_ERROR, "unsupported version\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (buf_size < header_size || header_size < XWD_HEADER_SIZE) {
          av_log(avctx, AV_LOG_ERROR, "invalid header size\n");
          return AVERROR_INVALIDDATA;
      }
  
      pixformat     = bytestream2_get_be32u(&gb);
      pixdepth      = bytestream2_get_be32u(&gb);
      avctx->width  = bytestream2_get_be32u(&gb);
      avctx->height = bytestream2_get_be32u(&gb);
      xoffset       = bytestream2_get_be32u(&gb);
      be            = bytestream2_get_be32u(&gb);
      bunit         = bytestream2_get_be32u(&gb);
      bitorder      = bytestream2_get_be32u(&gb);
      bpad          = bytestream2_get_be32u(&gb);
      bpp           = bytestream2_get_be32u(&gb);
      lsize         = bytestream2_get_be32u(&gb);
      vclass        = bytestream2_get_be32u(&gb);
      rgb[0]        = bytestream2_get_be32u(&gb);
      rgb[1]        = bytestream2_get_be32u(&gb);
      rgb[2]        = bytestream2_get_be32u(&gb);
      bytestream2_skipu(&gb, 8);
      ncolors       = bytestream2_get_be32u(&gb);
      bytestream2_skipu(&gb, header_size - (XWD_HEADER_SIZE - 20));
  
      av_log(avctx, AV_LOG_DEBUG, "pixformat %d, pixdepth %d, bunit %d, bitorder %d, bpad %d\n",
             pixformat, pixdepth, bunit, bitorder, bpad);
      av_log(avctx, AV_LOG_DEBUG, "vclass %d, ncolors %d, bpp %d, be %d, lsize %d, xoffset %d\n",
             vclass, ncolors, bpp, be, lsize, xoffset);
      av_log(avctx, AV_LOG_DEBUG, "red %0x, green %0x, blue %0x\n", rgb[0], rgb[1], rgb[2]);
  
      if (pixformat > XWD_Z_PIXMAP) {
          av_log(avctx, AV_LOG_ERROR, "invalid pixmap format\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (pixdepth == 0 || pixdepth > 32) {
          av_log(avctx, AV_LOG_ERROR, "invalid pixmap depth\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (xoffset) {
          avpriv_request_sample(avctx, "xoffset %d", xoffset);
          return AVERROR_PATCHWELCOME;
      }
  
      if (be > 1) {
          av_log(avctx, AV_LOG_ERROR, "invalid byte order\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (bitorder > 1) {
          av_log(avctx, AV_LOG_ERROR, "invalid bitmap bit order\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (bunit != 8 && bunit != 16 && bunit != 32) {
          av_log(avctx, AV_LOG_ERROR, "invalid bitmap unit\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (bpad != 8 && bpad != 16 && bpad != 32) {
          av_log(avctx, AV_LOG_ERROR, "invalid bitmap scan-line pad\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (bpp == 0 || bpp > 32) {
          av_log(avctx, AV_LOG_ERROR, "invalid bits per pixel\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (ncolors > 256) {
          av_log(avctx, AV_LOG_ERROR, "invalid number of entries in colormap\n");
          return AVERROR_INVALIDDATA;
      }
  
      if ((ret = av_image_check_size(avctx->width, avctx->height, 0, NULL)) < 0)
          return ret;
  
      rsize = FFALIGN(avctx->width * bpp, bpad) / 8;
      if (lsize < rsize) {
          av_log(avctx, AV_LOG_ERROR, "invalid bytes per scan-line\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (bytestream2_get_bytes_left(&gb) < ncolors * XWD_CMAP_SIZE + avctx->height * lsize) {
          av_log(avctx, AV_LOG_ERROR, "input buffer too small\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (pixformat != XWD_Z_PIXMAP) {
          av_log(avctx, AV_LOG_ERROR, "pixmap format %d unsupported\n", pixformat);
          return AVERROR_PATCHWELCOME;
      }
  
      avctx->pix_fmt = AV_PIX_FMT_NONE;
      switch (vclass) {
      case XWD_STATIC_GRAY:
      case XWD_GRAY_SCALE:
          if (bpp != 1 && bpp != 8)
              return AVERROR_INVALIDDATA;
          if (pixdepth == 1) {
              avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
          } else if (pixdepth == 8) {
              avctx->pix_fmt = AV_PIX_FMT_GRAY8;
          }
          break;
      case XWD_STATIC_COLOR:
      case XWD_PSEUDO_COLOR:
          if (bpp == 8)
              avctx->pix_fmt = AV_PIX_FMT_PAL8;
          break;
      case XWD_TRUE_COLOR:
      case XWD_DIRECT_COLOR:
          if (bpp != 16 && bpp != 24 && bpp != 32)
              return AVERROR_INVALIDDATA;
          if (bpp == 16 && pixdepth == 15) {
              if (rgb[0] == 0x7C00 && rgb[1] == 0x3E0 && rgb[2] == 0x1F)
                  avctx->pix_fmt = be ? AV_PIX_FMT_RGB555BE : AV_PIX_FMT_RGB555LE;
              else if (rgb[0] == 0x1F && rgb[1] == 0x3E0 && rgb[2] == 0x7C00)
                  avctx->pix_fmt = be ? AV_PIX_FMT_BGR555BE : AV_PIX_FMT_BGR555LE;
          } else if (bpp == 16 && pixdepth == 16) {
              if (rgb[0] == 0xF800 && rgb[1] == 0x7E0 && rgb[2] == 0x1F)
                  avctx->pix_fmt = be ? AV_PIX_FMT_RGB565BE : AV_PIX_FMT_RGB565LE;
              else if (rgb[0] == 0x1F && rgb[1] == 0x7E0 && rgb[2] == 0xF800)
                  avctx->pix_fmt = be ? AV_PIX_FMT_BGR565BE : AV_PIX_FMT_BGR565LE;
          } else if (bpp == 24) {
              if (rgb[0] == 0xFF0000 && rgb[1] == 0xFF00 && rgb[2] == 0xFF)
                  avctx->pix_fmt = be ? AV_PIX_FMT_RGB24 : AV_PIX_FMT_BGR24;
              else if (rgb[0] == 0xFF && rgb[1] == 0xFF00 && rgb[2] == 0xFF0000)
                  avctx->pix_fmt = be ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_RGB24;
          } else if (bpp == 32) {
              if (rgb[0] == 0xFF0000 && rgb[1] == 0xFF00 && rgb[2] == 0xFF)
                  avctx->pix_fmt = be ? AV_PIX_FMT_ARGB : AV_PIX_FMT_BGRA;
              else if (rgb[0] == 0xFF && rgb[1] == 0xFF00 && rgb[2] == 0xFF0000)
                  avctx->pix_fmt = be ? AV_PIX_FMT_ABGR : AV_PIX_FMT_RGBA;
          }
          bytestream2_skipu(&gb, ncolors * XWD_CMAP_SIZE);
          break;
      default:
          av_log(avctx, AV_LOG_ERROR, "invalid visual class\n");
          return AVERROR_INVALIDDATA;
      }
  
      if (avctx->pix_fmt == AV_PIX_FMT_NONE) {
          avpriv_request_sample(avctx,
                                "Unknown file: bpp %d, pixdepth %d, vclass %d",
                                bpp, pixdepth, vclass);
          return AVERROR_PATCHWELCOME;
      }
  
      if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
          return ret;
  
      p->key_frame = 1;
      p->pict_type = AV_PICTURE_TYPE_I;
  
      if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
          uint32_t *dst = (uint32_t *)p->data[1];
          uint8_t red, green, blue;
  
          for (i = 0; i < ncolors; i++) {
  
              bytestream2_skipu(&gb, 4); // skip colormap entry number
              red    = bytestream2_get_byteu(&gb);
              bytestream2_skipu(&gb, 1);
              green  = bytestream2_get_byteu(&gb);
              bytestream2_skipu(&gb, 1);
              blue   = bytestream2_get_byteu(&gb);
              bytestream2_skipu(&gb, 3); // skip bitmask flag and padding
  
              dst[i] = red << 16 | green << 8 | blue;
          }
      }
  
      ptr = p->data[0];
      for (i = 0; i < avctx->height; i++) {
          bytestream2_get_bufferu(&gb, ptr, rsize);
          bytestream2_skipu(&gb, lsize - rsize);
          ptr += p->linesize[0];
      }
  
      *got_frame       = 1;
  
      return buf_size;
  }
  
  AVCodec ff_xwd_decoder = {
      .name           = "xwd",
      .type           = AVMEDIA_TYPE_VIDEO,
      .id             = AV_CODEC_ID_XWD,
      .decode         = xwd_decode_frame,
      .capabilities   = CODEC_CAP_DR1,
      .long_name      = NULL_IF_CONFIG_SMALL("XWD (X Window Dump) image"),
  };
  