yading@10: /*
yading@10:  * common code shared by all WMA variants
yading@10:  *
yading@10:  * This file is part of Libav.
yading@10:  *
yading@10:  * Libav is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * Libav is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with Libav; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "libavutil/attributes.h"
yading@10: #include "wma_common.h"
yading@10: 
yading@10: /**
yading@10:  *@brief Get the samples per frame for this stream.
yading@10:  *@param sample_rate output sample_rate
yading@10:  *@param version wma version
yading@10:  *@param decode_flags codec compression features
yading@10:  *@return log2 of the number of output samples per frame
yading@10:  */
yading@10: av_cold int ff_wma_get_frame_len_bits(int sample_rate, int version,
yading@10:                                       unsigned int decode_flags)
yading@10: {
yading@10: 
yading@10:     int frame_len_bits;
yading@10: 
yading@10:     if (sample_rate <= 16000) {
yading@10:         frame_len_bits = 9;
yading@10:     } else if (sample_rate <= 22050 ||
yading@10:              (sample_rate <= 32000 && version == 1)) {
yading@10:         frame_len_bits = 10;
yading@10:     } else if (sample_rate <= 48000 || version < 3) {
yading@10:         frame_len_bits = 11;
yading@10:     } else if (sample_rate <= 96000) {
yading@10:         frame_len_bits = 12;
yading@10:     } else {
yading@10:         frame_len_bits = 13;
yading@10:     }
yading@10: 
yading@10:     if (version == 3) {
yading@10:         int tmp = decode_flags & 0x6;
yading@10:         if (tmp == 0x2) {
yading@10:             ++frame_len_bits;
yading@10:         } else if (tmp == 0x4) {
yading@10:             --frame_len_bits;
yading@10:         } else if (tmp == 0x6) {
yading@10:             frame_len_bits -= 2;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return frame_len_bits;
yading@10: }