dds: Add support for rgb555 files

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

libavcodec/dds.c

@@ -357,6 +357,10 @@ static int parse_pixel_format(AVCodecContext *avctx)
             avctx->pix_fmt = AV_PIX_FMT_YA8;
         else if (bpp == 16 && r == 0xffff && g == 0 && b == 0 && a == 0)
             avctx->pix_fmt = AV_PIX_FMT_GRAY16LE;
+        else if (bpp == 16 && r == 0x7c00 && g == 0x3e0 && b == 0x1f && a == 0)
+            avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
+        else if (bpp == 16 && r == 0x7c00 && g == 0x3e0 && b == 0x1f && a == 0x8000)
+            avctx->pix_fmt = AV_PIX_FMT_RGB555LE; // alpha ignored
         else if (bpp == 16 && r == 0xf800 && g == 0x7e0 && b == 0x1f && a == 0)
             avctx->pix_fmt = AV_PIX_FMT_RGB565LE;
         /* 24 bpp */