modules/codec/xwd.c

   1 /*****************************************************************************
   2  * xwd.c: X Window system raster image dump pseudo-decoder
   3  *****************************************************************************
   4  * Copyright (C) 2012 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <assert.h>
  26 #ifdef HAVE_ARPA_INET_H
  27 #include <arpa/inet.h>
  28 #endif
  29 #include <X11/XWDFile.h>
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_codec.h>
  34
  35 static int Decode (decoder_t *dec, block_t *block)
  36 {
  37     picture_t *pic = NULL;
  38
  39     if (block == NULL) /* No Drain */
  40         return VLCDEC_SUCCESS;
  41
  42     if (block->i_pts == VLC_TICK_INVALID)
  43         goto drop; /* undated block, should never happen */
  44     if (block->i_buffer < sz_XWDheader)
  45         goto drop;
  46
  47     /* Skip XWD header */
  48     const XWDFileHeader *hdr = (const void *)block->p_buffer;
  49     uint32_t hdrlen = ntohl(hdr->header_size);
  50     if (hdrlen < sz_XWDheader
  51      || ntohl(hdr->file_version) < XWD_FILE_VERSION
  52      || ntohl(hdr->pixmap_format) != 2 /* ZPixmap */)
  53         goto drop;
  54
  55     hdrlen += ntohl(hdr->ncolors) * sz_XWDColor;
  56     if (hdrlen > block->i_buffer)
  57         goto drop;
  58     block->p_buffer += hdrlen;
  59     block->i_buffer -= hdrlen;
  60
  61     /* Parse XWD header */
  62     vlc_fourcc_t chroma = 0;
  63     switch (ntohl(hdr->pixmap_depth))
  64     {
  65         case 8:
  66             if (ntohl(hdr->bits_per_pixel) == 8)
  67                 chroma = VLC_CODEC_RGB8;
  68             break;
  69         case 15:
  70             if (ntohl(hdr->bits_per_pixel) == 16)
  71                 chroma = VLC_CODEC_RGB15;
  72             break;
  73         case 16:
  74             if (ntohl(hdr->bits_per_pixel) == 16)
  75                 chroma = VLC_CODEC_RGB16;
  76             break;
  77         case 24:
  78             switch (ntohl(hdr->bits_per_pixel))
  79             {
  80                 case 32: chroma = VLC_CODEC_RGB32; break;
  81                 case 24: chroma = VLC_CODEC_RGB24; break;
  82             }
  83             break;
  84         case 32:
  85             if (ntohl(hdr->bits_per_pixel) == 32)
  86                 chroma = VLC_CODEC_ARGB;
  87             break;
  88     }
  89     /* TODO: check image endianess, set RGB mask */
  90     if (!chroma)
  91         goto drop;
  92
  93     video_format_Setup(&dec->fmt_out.video, chroma,
  94                        ntohl(hdr->pixmap_width), ntohl(hdr->pixmap_height),
  95                        ntohl(hdr->pixmap_width), ntohl(hdr->pixmap_height),
  96                        dec->fmt_in.video.i_sar_num,
  97                        dec->fmt_in.video.i_sar_den);
  98
  99     const size_t copy = dec->fmt_out.video.i_width
 100                         * (dec->fmt_out.video.i_bits_per_pixel / 8);
 101     const uint32_t pitch = ntohl(hdr->bytes_per_line);
 102
 103     /* Build picture */
 104     if (pitch < copy
 105      || (block->i_buffer / pitch) < dec->fmt_out.video.i_height)
 106         goto drop;
 107
 108     if (decoder_UpdateVideoFormat(dec))
 109         goto drop;
 110     pic = decoder_NewPicture(dec);
 111     if (pic == NULL)
 112         goto drop;
 113
 114     const uint8_t *in = block->p_buffer;
 115     uint8_t *out = pic->p->p_pixels;
 116     for (unsigned i = 0; i < dec->fmt_out.video.i_height; i++)
 117     {
 118         memcpy(out, in, copy);
 119         in += pitch;
 120         out += pic->p->i_pitch;
 121     }
 122     pic->date = block->i_pts;
 123     pic->b_progressive = true;
 124
 125 drop:
 126     block_Release(block);
 127     decoder_QueueVideo(dec, pic);
 128     return VLCDEC_SUCCESS;
 129 }
 130
 131 static int Open(vlc_object_t *obj)
 132 {
 133     decoder_t *dec = (decoder_t *)obj;
 134
 135     if (dec->fmt_in.i_codec != VLC_CODEC_XWD)
 136         return VLC_EGENERIC;
 137
 138     dec->pf_decode = Decode;
 139     es_format_Copy(&dec->fmt_out, &dec->fmt_in);
 140     dec->fmt_out.i_codec = VLC_CODEC_RGB32;
 141     return VLC_SUCCESS;
 142 }
 143
 144 vlc_module_begin()
 145     set_description(N_("XWD image decoder"))
 146     set_capability("video decoder", 50)
 147     set_category(CAT_INPUT)
 148     set_subcategory(SUBCAT_INPUT_VCODEC)
 149     set_callback(Open)
 150 vlc_module_end()