[MPlayer-dev-eng] Re: Question about lavcopts's aspect= option

[Rémi Guyomarch]

On Tue, Nov 19, 2002 at 07:06:54PM +0100, Gabucino wrote:
> I can't get this sucker to work as it should.
> I wanted to encode my 480x280 MPEG movie (with aspect 1.33 = 640x280) to

Neither 480x280 or 640x280 has a 4:3 aspect ratio.

Aspect ratio = displayed width / displayed height. In your case you
want an aspect ratio of 16/7 or ~2.29.

> MPEG4, using libavcodec's aspect info storing feature, only to found that
> only 4:3, 16:9, and 221:100 (??!!) are supported. 

Yes. This short-term patch fix it, although it's not the right way to
do that IMHO :

--- libmpcodecs/ve_lavc.c	14 Nov 2002 22:36:16 -0000	1.39
+++ libmpcodecs/ve_lavc.c	20 Nov 2002 05:37:42 -0000
@@ -297,15 +297,11 @@
 	    lavc_venc_context->aspect_ratio_info = FF_ASPECT_4_3_625;
 	else if (lavc_param_aspect == (float)(16.0/9.0))
 	    lavc_venc_context->aspect_ratio_info = FF_ASPECT_16_9_625;
-	else if (lavc_param_aspect == (float)(221.0/100.0))
+	else
 	{
     	    lavc_venc_context->aspect_ratio_info = FF_ASPECT_EXTENDED;
-	    lavc_venc_context->aspected_width = 221;
+	    lavc_venc_context->aspected_width = lavc_param_aspect * 100 + 0.5;
 	    lavc_venc_context->aspected_height = 100;
-	}
-	else
-	{
-	    printf("Unsupported aspect ratio (%f)\n", lavc_param_aspect);
 	}
 	mp_dbg(MSGT_MENCODER, MSGL_DBG2, "aspect_ratio_info: %d\n", lavc_venc_context->aspect_ratio_info);
 	mp_dbg(MSGT_MENCODER, MSGL_DBG2, "par_width: %d\n", lavc_venc_context->aspected_width);


> I'd need 16:12.
> 
> Just how can I achieve that?

16:12 == 4:3 :-)
But in fact you need 16:7.

-- 
Rémi