gstreamer/gst/mpegtsmux/mpegtsmux_aac.c
2011-05-18 12:06:38 -07:00

149 lines
5.9 KiB
C

/*
* Copyright 2006, 2007, 2008 Fluendo S.A.
* Authors: Jan Schmidt <jan@fluendo.com>
* Kapil Agrawal <kapil@fluendo.com>
* Julien Moutte <julien@fluendo.com>
*
* This library is licensed under 4 different licenses and you
* can choose to use it under the terms of any one of them. The
* four licenses are the MPL 1.1, the LGPL, the GPL and the MIT
* license.
*
* MPL:
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* LGPL:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* GPL:
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* MIT:
*
* Unless otherwise indicated, Source Code is licensed under MIT license.
* See further explanation attached in License Statement (distributed in the file
* LICENSE).
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "mpegtsmux_aac.h"
#include <string.h>
#define GST_CAT_DEFAULT mpegtsmux_debug
GstBuffer *
mpegtsmux_prepare_aac (GstBuffer * buf, MpegTsPadData * data, MpegTsMux * mux)
{
guint8 adts_header[7] = { 0, };
GstBuffer *out_buf = gst_buffer_new_and_alloc (GST_BUFFER_SIZE (buf) + 7);
gsize out_offset = 0;
guint8 rate_idx = 0, channels = 0, obj_type = 0;
GST_DEBUG_OBJECT (mux, "Preparing AAC buffer for output");
/* We want the same metadata */
gst_buffer_copy_metadata (out_buf, buf, GST_BUFFER_COPY_ALL);
/* Generate ADTS header */
obj_type = (GST_READ_UINT8 (GST_BUFFER_DATA (data->codec_data)) & 0xC) >> 2;
obj_type++;
rate_idx = (GST_READ_UINT8 (GST_BUFFER_DATA (data->codec_data)) & 0x3) << 1;
rate_idx |=
(GST_READ_UINT8 (GST_BUFFER_DATA (data->codec_data) + 1) & 0x80) >> 7;
channels =
(GST_READ_UINT8 (GST_BUFFER_DATA (data->codec_data) + 1) & 0x78) >> 3;
GST_DEBUG_OBJECT (mux, "Rate index %u, channels %u, object type %u", rate_idx,
channels, obj_type);
/* Sync point over a full byte */
adts_header[0] = 0xFF;
/* Sync point continued over first 4 bits + static 4 bits
* (ID, layer, protection)*/
adts_header[1] = 0xF1;
/* Object type over first 2 bits */
adts_header[2] = obj_type << 6;
/* rate index over next 4 bits */
adts_header[2] |= (rate_idx << 2);
/* channels over last 2 bits */
adts_header[2] |= (channels & 0x4) >> 2;
/* channels continued over next 2 bits + 4 bits at zero */
adts_header[3] = (channels & 0x3) << 6;
/* frame size over last 2 bits */
adts_header[3] |= (GST_BUFFER_SIZE (out_buf) & 0x1800) >> 11;
/* frame size continued over full byte */
adts_header[4] = (GST_BUFFER_SIZE (out_buf) & 0x1FF8) >> 3;
/* frame size continued first 3 bits */
adts_header[5] = (GST_BUFFER_SIZE (out_buf) & 0x7) << 5;
/* buffer fullness (0x7FF for VBR) over 5 last bits */
adts_header[5] |= 0x1F;
/* buffer fullness (0x7FF for VBR) continued over 6 first bits + 2 zeros for
* number of raw data blocks */
adts_header[6] = 0xFC;
/* Insert ADTS header */
memcpy (GST_BUFFER_DATA (out_buf) + out_offset, adts_header, 7);
out_offset += 7;
/* Now copy complete frame */
memcpy (GST_BUFFER_DATA (out_buf) + out_offset, GST_BUFFER_DATA (buf),
GST_BUFFER_SIZE (buf));
return out_buf;
}