aac plugin

git-svn-id: http://svn.code.sf.net/p/qmmp-dev/code/trunk/qmmp@601 90c681e8-e032-0410-971d-27865f9a5e38

1 files changed, 120 insertions, 0 deletions

diff --git a/src/plugins/Input/aac/aacfile.cpp b/src/plugins/Input/aac/aacfile.cpp
new file mode 100644
index 000000000..9cf3184d8
--- /dev/null
+++ b/src/plugins/Input/aac/aacfile.cpp
@@ -0,0 +1,120 @@
+/***************************************************************************
+ *   Copyright (C) 2008 by Ilya Kotov                                      *
+ *   forkotov02@hotmail.ru                                                 *
+ *                                                                         *
+ *   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.             *
+ ***************************************************************************/
+
+#include <QIODevice>
+
+#include <neaacdec.h>
+
+#include "aacfile.h"
+
+#define MAX_CHANNELS 6
+
+static int adts_sample_rates[] = {96000,88200,64000,48000,44100,32000,24000,22050,16000,12000,11025,8000,7350,0,0,0};
+
+AACFile::AACFile(QIODevice *i)
+{
+    m_length = 0;
+    m_bitrate = 0;
+    m_input = i;
+    parseADTS();
+}
+
+AACFile::~AACFile()
+{
+}
+
+qint64 AACFile::length()
+{
+    return m_length;
+}
+
+quint32 AACFile::bitrate()
+{
+    return m_bitrate;
+}
+
+void AACFile::parseADTS()
+{
+    uchar *buf = new uchar[FAAD_MIN_STREAMSIZE*MAX_CHANNELS];
+    qint64 buf_at = 0;
+    int frames, frame_length;
+    int t_framelength = 0;
+    int samplerate = 0;
+    float frames_per_sec, bytes_per_frame;
+    qint64 pos = m_input->pos();
+
+    m_input->seek(0);
+
+    buf_at = m_input->read((char *)buf, FAAD_MIN_STREAMSIZE*MAX_CHANNELS);
+
+    for (int i = 0; i < buf_at - 1; i++)
+    {
+        if (buf[i] == 0xff && (buf[i+1]&0xf6) == 0xf0)
+        {
+            memmove (buf, buf + i, buf_at - i);
+            buf_at -= i;
+            break;
+        }
+    }
+
+    /* Read all frames to ensure correct time and bitrate */
+    for (frames = 0; /* */; frames++)
+    {
+        //qDebug("frame header = %d", buf[0]);
+        buf_at += m_input->read((char *)buf + buf_at, FAAD_MIN_STREAMSIZE*MAX_CHANNELS - buf_at);
+
+        if (buf_at > 7)
+        {
+            /* check syncword */
+            if (!((buf[0] == 0xFF)&&((buf[1] & 0xF6) == 0xF0)))
+                break;
+
+            if (frames == 0)
+                samplerate = adts_sample_rates[(buf[2]&0x3c)>>2];
+
+            frame_length = ((((unsigned int)buf[3] & 0x3)) << 11)
+                           | (((unsigned int)buf[4]) << 3) | (buf[5] >> 5);
+
+            t_framelength += frame_length;
+
+            if (frame_length > buf_at)
+                break;
+
+            buf_at -= frame_length;
+            memmove(buf, buf + frame_length, buf_at);
+        }
+        else
+        {
+            break;
+        }
+    }
+    m_input->seek(pos);
+    frames_per_sec = (float)samplerate/1024.0f;
+    if (frames != 0)
+        bytes_per_frame = (float)t_framelength/(float)(frames*1000);
+    else
+        bytes_per_frame = 0;
+    m_bitrate = (quint32)(8. * bytes_per_frame * frames_per_sec + 0.5);
+
+    if (frames_per_sec != 0)
+        m_length = frames/frames_per_sec;
+    else
+        m_length = 1;
+}