FFmpeg: libavcodec/flac.c Source File

00001 /*
00002  * FLAC common code
00003  * Copyright (c) 2009 Justin Ruggles
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "flac.h"
00023 
00024 int ff_flac_get_max_frame_size(int blocksize, int ch, int bps)
00025 {
00026     /* Technically, there is no limit to FLAC frame size, but an encoder
00027        should not write a frame that is larger than if verbatim encoding mode
00028        were to be used. */
00029 
00030     int count;
00031 
00032     count = 16;                  /* frame header */
00033     count += ch * ((7+bps+7)/8); /* subframe headers */
00034     if (ch == 2) {
00035         /* for stereo, need to account for using decorrelation */
00036         count += (( 2*bps+1) * blocksize + 7) / 8;
00037     } else {
00038         count += ( ch*bps    * blocksize + 7) / 8;
00039     }
00040     count += 2; /* frame footer */
00041 
00042     return count;
00043 }