viddec: keeps the same aspect ratio for width and height when resizing

Signed-off-by: Jean-Paul Saman <jean-paul.saman@m2x.nl>

modules/codec/davinci/viddec.c

@@ -85,6 +85,24 @@ struct decoder_sys_t
 
 
 #ifdef DAVINCI_HACK
+static void Resize( unsigned int *i_width, unsigned int *i_height,
+                    unsigned int i_vidw, unsigned int i_vidh )
+{
+    unsigned int i_hratio = VOUT_ASPECT_FACTOR * *i_height / i_vidh;
+    unsigned int i_wratio = VOUT_ASPECT_FACTOR * *i_width / i_vidw;
+
+    if( i_hratio == i_wratio )
+        return; /* nothing to do */
+
+    /* else choose the minimum for both axes */
+    i_hratio = i_wratio = i_hratio < i_wratio ? i_hratio : i_wratio;
+
+    /* and set the new resolution accordingly */
+    *i_height = (i_vidh * i_hratio) / VOUT_ASPECT_FACTOR;
+    *i_width = (i_vidw * i_wratio) / VOUT_ASPECT_FACTOR;
+}
+
+/* open() a framebuffer by its name (NOT device path) */
 static int OpenFB( const char *psz_name )
 {
     int i_fd = -1;
@@ -715,8 +733,12 @@ static picture_t *DecodeVideoBlockInner( decoder_t *p_dec, block_t **pp_block, i
             (p_dec->fmt_out.video.i_width * BPP / 8 + 31) & ~31;
         rsz_params.inptyp = RSZ_INTYPE_YCBCR422_16BIT;
         rsz_params.pix_fmt = RSZ_PIX_FMT_YUYV;
+        /* Sets the destination resolution */
         rsz_params.out_hsize = p_sys->var_info.xres;
         rsz_params.out_vsize = p_sys->var_info.yres;
+        /* And then modify it to keep the same aspect ratio */
+        Resize( &rsz_params.out_hsize, &rsz_params.out_vsize,
+                p_dec->fmt_out.video.i_width, p_dec->fmt_out.video.i_height );
         rsz_params.out_pitch = p_sys->fix_info.line_length;
 
         short hcoefs[32] = {