From owner-freebsd-multimedia Sun Nov 9 19:36:24 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id TAA28755 for multimedia-outgoing; Sun, 9 Nov 1997 19:36:24 -0800 (PST) (envelope-from owner-freebsd-multimedia) Received: from rah.star-gate.com (rah.star-gate.com [204.188.121.18]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id TAA28739 for ; Sun, 9 Nov 1997 19:36:17 -0800 (PST) (envelope-from hasty@rah.star-gate.com) Received: from rah.star-gate.com (localhost.v-site.net [127.0.0.1]) by rah.star-gate.com (8.8.7/8.8.5) with ESMTP id TAA00860; Sun, 9 Nov 1997 19:36:14 -0800 (PST) Message-Id: <199711100336.TAA00860@rah.star-gate.com> X-Mailer: exmh version 2.0zeta 7/24/97 To: multimedia@freebsd.org cc: rhh@ct.picker.com Subject: yuv support for mpeg Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sun, 09 Nov 1997 19:36:14 -0800 From: Amancio Hasty Sender: owner-freebsd-multimedia@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Why yuv for mpeg encoding? Well, if you try to use fxtv to encode mpeg files the disk requirement is width * height * 16 * 2 per frame vs (width * height + (width * height) / 2). Where we get a big hit is on the disk requirement . fxtv first saves the video stream in raw format then it converts to tiff or ppm which doubles the disk requirement. Additionally, it takes time to convert the raw video stream to ppm or tiff format. Last but not least the thruput requirement for the disk is less than for raw video format which is (width*height*2) * 30 / sec. ftp://rah.star-gate.com/pub/bt848-yuv.tar.gz The tar contains yuv12capture.c a sample program on how to capture yuv and mpeg_encode's param file, foo.param. to encode: cat file | mpeg_encode foo.param I will check in the yuv12 support on Wednesday hopefully after the current round of bt848 patches have been checked in. If it should prove that YUV support for FXTV is tedious to add I will extend and enhance slightly yuv12capture.c to support both video and audio. Enjoy, Amancio