Now commit the actual dir

mp4ff/Makefile.am

+noinst_LTLIBRARIES = libmp4ff.la
+
+noinst_HEADERS = mp4ff.h
+
+libmp4ff_la_SOURCES = mp4ff.c mp4atom.c mp4meta.c mp4sample.c mp4util.c \
+   mp4tagupdate.c mp4ff.h mp4ffint.h mp4ff_int_types.h \
+   drms.h drms.c drmstables.h
+
+AM_CFLAGS = -DUSE_TAGGING=1

mp4ff/drms.h

+/*****************************************************************************
+ * drms.h : DRMS
+ *****************************************************************************
+ * Copyright (C) 2004 VideoLAN
+ * $Id: drms.h,v 1.3 2004/01/11 15:52:18 menno Exp $
+ *
+ * Author: Jon Lech Johansen <jon-vl@nanocrew.net>
+ *
+ * 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, USA.
+ *****************************************************************************/
+
+
+#define DRMS_INIT_UKEY  0
+#define DRMS_INIT_IVIV  1
+#define DRMS_INIT_NAME  2
+#define DRMS_INIT_PRIV  3
+
+extern int drms_get_sys_key( uint32_t *p_sys_key );
+extern int drms_get_user_key( uint32_t *p_sys_key,
+                              uint32_t *p_user_key );
+
+extern void *drms_alloc();
+extern void drms_free( void *p_drms );
+extern int drms_init( void *p_drms, uint32_t i_type,
+                      uint8_t *p_info, uint32_t i_len );
+extern void drms_decrypt( void *p_drms, uint32_t *p_buffer,
+                          uint32_t i_len );
+

mp4ff/mp4ff.dsp

+# Microsoft Developer Studio Project File - Name="mp4ff" - Package Owner=<4>
+# Microsoft Developer Studio Generated Build File, Format Version 6.00
+# ** DO NOT EDIT **
+
+# TARGTYPE "Win32 (x86) Static Library" 0x0104
+
+CFG=mp4ff - Win32 Debug
+!MESSAGE This is not a valid makefile. To build this project using NMAKE,
+!MESSAGE use the Export Makefile command and run
+!MESSAGE 
+!MESSAGE NMAKE /f "mp4ff.mak".
+!MESSAGE 
+!MESSAGE You can specify a configuration when running NMAKE
+!MESSAGE by defining the macro CFG on the command line. For example:
+!MESSAGE 
+!MESSAGE NMAKE /f "mp4ff.mak" CFG="mp4ff - Win32 Debug"
+!MESSAGE 
+!MESSAGE Possible choices for configuration are:
+!MESSAGE 
+!MESSAGE "mp4ff - Win32 Release" (based on "Win32 (x86) Static Library")
+!MESSAGE "mp4ff - Win32 Debug" (based on "Win32 (x86) Static Library")
+!MESSAGE 
+
+# Begin Project
+# PROP AllowPerConfigDependencies 0
+# PROP Scc_ProjName ""
+# PROP Scc_LocalPath ""
+CPP=xicl6.exe
+RSC=rc.exe
+
+!IF  "$(CFG)" == "mp4ff - Win32 Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "Release"
+# PROP BASE Intermediate_Dir "Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Release"
+# PROP Intermediate_Dir "Release"
+# PROP Target_Dir ""
+F90=df.exe
+MTL=midl.exe
+# ADD BASE CPP /nologo /W3 /GX /O2 /D "WIN32" /D "NDEBUG" /D "_WINDOWS" /YX /FD /c
+# ADD CPP /nologo /MD /W3 /O1 /D "NDEBUG" /D "WIN32" /D "_WINDOWS" /D "USE_TAGGING" /YX /FD /c
+# ADD BASE RSC /l 0x413 /d "NDEBUG"
+# ADD RSC /l 0x413 /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=xilink6.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo
+
+!ELSEIF  "$(CFG)" == "mp4ff - Win32 Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "Debug"
+# PROP BASE Intermediate_Dir "Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Debug"
+# PROP Intermediate_Dir "Debug"
+# PROP Target_Dir ""
+F90=df.exe
+MTL=midl.exe
+# ADD BASE CPP /nologo /W3 /Gm /GX /ZI /Od /D "WIN32" /D "_DEBUG" /D "_WINDOWS" /YX /FD /GZ /c
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "_DEBUG" /D "WIN32" /D "_WINDOWS" /D "USE_TAGGING" /YX /FD /GZ /c
+# ADD BASE RSC /l 0x413 /d "_DEBUG"
+# ADD RSC /l 0x413 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=xilink6.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo
+
+!ENDIF 
+
+# Begin Target
+
+# Name "mp4ff - Win32 Release"
+# Name "mp4ff - Win32 Debug"
+# Begin Group "Source Files"
+
+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"
+# Begin Source File
+
+SOURCE=.\drms.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4atom.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4ff.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4meta.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4sample.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4tagupdate.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4util.c
+# End Source File
+# End Group
+# Begin Group "Header Files"
+
+# PROP Default_Filter "h;hpp;hxx;hm;inl"
+# Begin Source File
+
+SOURCE=.\drms.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\drmstables.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4ff.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4ff_int_types.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\mp4ffint.h
+# End Source File
+# End Group
+# End Target
+# End Project

mp4ff/mp4ff.h

+/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
+**
+** 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.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
+**
+** $Id: mp4ff.h,v 1.19 2004/01/11 15:52:18 menno Exp $
+**/
+
+#ifndef MP4FF_H
+#define MP4FF_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#include "mp4ff_int_types.h"
+
+/* file callback structure */
+typedef struct
+{
+    uint32_t (*read)(void *user_data, void *buffer, uint32_t length);
+    uint32_t (*write)(void *udata, void *buffer, uint32_t length);
+    uint32_t (*seek)(void *user_data, uint64_t position);
+	uint32_t (*truncate)(void *user_data);
+    void *user_data;
+} mp4ff_callback_t;
+
+/* mp4 main file structure */
+typedef void* mp4ff_t;
+
+
+/* API */
+
+mp4ff_t *mp4ff_open_read(mp4ff_callback_t *f);
+void mp4ff_close(mp4ff_t *f);
+int32_t mp4ff_get_sample_duration(const mp4ff_t *f, const int32_t track, const int32_t sample);
+int32_t mp4ff_get_sample_duration_use_offsets(const mp4ff_t *f, const int32_t track, const int32_t sample);
+int64_t mp4ff_get_sample_position(const mp4ff_t *f, const int32_t track, const int32_t sample);
+int32_t mp4ff_get_sample_offset(const mp4ff_t *f, const int32_t track, const int32_t sample);
+int32_t mp4ff_find_sample(const mp4ff_t *f, const int32_t track, const int64_t offset,int32_t * toskip);
+int32_t mp4ff_find_sample_use_offsets(const mp4ff_t *f, const int32_t track, const int64_t offset,int32_t * toskip);
+
+int32_t mp4ff_read_sample(mp4ff_t *f, const int track, const int sample,
+                          unsigned char **audio_buffer,  unsigned int *bytes);
+
+int32_t mp4ff_read_sample_v2(mp4ff_t *f, const int track, const int sample,unsigned char *buffer);//returns 0 on error, number of bytes read on success, use mp4ff_read_sample_getsize() to check buffer size needed
+int32_t mp4ff_read_sample_getsize(mp4ff_t *f, const int track, const int sample);//returns 0 on error, buffer size needed for mp4ff_read_sample_v2() on success
+
+
+
+int32_t mp4ff_get_decoder_config(const mp4ff_t *f, const int track,
+                             unsigned char** ppBuf, unsigned int* pBufSize);
+int32_t mp4ff_get_track_type(const mp4ff_t *f, const int track);
+int32_t mp4ff_total_tracks(const mp4ff_t *f);
+int32_t mp4ff_num_samples(const mp4ff_t *f, const int track);
+int32_t mp4ff_time_scale(const mp4ff_t *f, const int track);
+
+uint32_t mp4ff_get_avg_bitrate(const mp4ff_t *f, const int32_t track);
+uint32_t mp4ff_get_max_bitrate(const mp4ff_t *f, const int32_t track);
+int64_t mp4ff_get_track_duration(const mp4ff_t *f, const int32_t track); //returns (-1) if unknown
+int64_t mp4ff_get_track_duration_use_offsets(const mp4ff_t *f, const int32_t track); //returns (-1) if unknown
+uint32_t mp4ff_get_sample_rate(const mp4ff_t *f, const int32_t track);
+uint32_t mp4ff_get_channel_count(const mp4ff_t * f,const int32_t track);
+uint32_t mp4ff_get_audio_type(const mp4ff_t * f,const int32_t track);
+
+
+/* metadata */
+int mp4ff_meta_get_num_items(const mp4ff_t *f);
+int mp4ff_meta_get_by_index(const mp4ff_t *f, unsigned int index,
+                            char **item, char **value);
+int mp4ff_meta_get_title(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_artist(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_writer(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_album(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_date(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_tool(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_comment(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_genre(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_track(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_disc(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_compilation(const mp4ff_t *f, char **value);
+int mp4ff_meta_get_tempo(const mp4ff_t *f, char **value);
+int32_t mp4ff_meta_get_coverart(const mp4ff_t *f, char **value);
+#ifdef USE_TAGGING
+
+/* metadata tag structure */
+typedef struct
+{
+    char *item;
+    char *value;
+} mp4ff_tag_t;
+
+/* metadata list structure */
+typedef struct
+{
+    mp4ff_tag_t *tags;
+    uint32_t count;
+} mp4ff_metadata_t;
+
+int32_t mp4ff_meta_update(mp4ff_callback_t *f,const mp4ff_metadata_t * data);
+
+#endif
+
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif

mp4ff/mp4ff_int_types.h

+#ifndef _MP4FF_INT_TYPES_H_
+#define _MP4FF_INT_TYPES_H_
+
+#ifdef _WIN32
+
+typedef char int8_t;
+typedef unsigned char uint8_t;
+typedef short int16_t;
+typedef unsigned short uint16_t;
+typedef long int32_t;
+typedef unsigned long uint32_t;
+
+typedef __int64 int64_t;
+typedef unsigned __int64 uint64_t;
+
+#else
+
+#include "config.h"
+
+#if defined(HAVE_STDINT_H)
+#include <stdint.h>
+#elif defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#elif defined(HAVE_SYS_INTTYPES_H)
+#include <sys/inttypes.h>
+#elif defined(HAVE_SYS_TYPES_H)
+#include <sys/types.h>
+#endif
+
+#endif
+
+#endif

mp4ff/mp4sample.c

+/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
+**
+** 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.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
+**
+** $Id: mp4sample.c,v 1.15 2004/01/11 15:52:19 menno Exp $
+**/
+
+#include <stdlib.h>
+#include "mp4ffint.h"
+
+
+static int32_t mp4ff_chunk_of_sample(const mp4ff_t *f, const int32_t track, const int32_t sample,
+                                     int32_t *chunk_sample, int32_t *chunk)
+{
+    int32_t total_entries = 0;
+    int32_t chunk2entry;
+    int32_t chunk1, chunk2, chunk1samples, range_samples, total = 0;
+
+    if (f->track[track] == NULL)
+    {
+        return -1;
+    }
+
+    total_entries = f->track[track]->stsc_entry_count;
+
+    chunk1 = 1;
+    chunk1samples = 0;
+    chunk2entry = 0;
+
+    do
+    {
+        chunk2 = f->track[track]->stsc_first_chunk[chunk2entry];
+        *chunk = chunk2 - chunk1;
+        range_samples = *chunk * chunk1samples;
+
+        if (sample < total + range_samples) break;
+
+        chunk1samples = f->track[track]->stsc_samples_per_chunk[chunk2entry];
+        chunk1 = chunk2;
+
+        if(chunk2entry < total_entries)
+        {
+            chunk2entry++;
+            total += range_samples;
+        }
+    } while (chunk2entry < total_entries);
+
+    if (chunk1samples)
+        *chunk = (sample - total) / chunk1samples + chunk1;
+    else
+        *chunk = 1;
+
+    *chunk_sample = total + (*chunk - chunk1) * chunk1samples;
+
+    return 0;
+}
+
+static int32_t mp4ff_chunk_to_offset(const mp4ff_t *f, const int32_t track, const int32_t chunk)
+{
+    const mp4ff_track_t * p_track = f->track[track];
+
+    if (p_track->stco_entry_count && (chunk > p_track->stco_entry_count))
+    {
+        return p_track->stco_chunk_offset[p_track->stco_entry_count - 1];
+    } else if (p_track->stco_entry_count) {
+        return p_track->stco_chunk_offset[chunk - 1];
+    } else {
+        return 8;
+    }
+
+    return 0;
+}
+
+static int32_t mp4ff_sample_range_size(const mp4ff_t *f, const int32_t track,
+                                       const int32_t chunk_sample, const int32_t sample)
+{
+    int32_t i, total;
+    const mp4ff_track_t * p_track = f->track[track];
+
+    if (p_track->stsz_sample_size)
+    {
+        return (sample - chunk_sample) * p_track->stsz_sample_size;
+    }
+    else
+    {
+        if (sample>=p_track->stsz_sample_count) return 0;//error
+
+        for(i = chunk_sample, total = 0; i < sample; i++)
+        {
+            total += p_track->stsz_table[i];
+        }
+    }
+
+    return total;
+}
+
+static int32_t mp4ff_sample_to_offset(const mp4ff_t *f, const int32_t track, const int32_t sample)
+{
+    int32_t chunk, chunk_sample, chunk_offset1, chunk_offset2;
+
+    mp4ff_chunk_of_sample(f, track, sample, &chunk_sample, &chunk);
+
+    chunk_offset1 = mp4ff_chunk_to_offset(f, track, chunk);
+    chunk_offset2 = chunk_offset1 + mp4ff_sample_range_size(f, track, chunk_sample, sample);
+
+    return chunk_offset2;
+}
+
+int32_t mp4ff_audio_frame_size(const mp4ff_t *f, const int32_t track, const int32_t sample)
+{
+    int32_t bytes;
+    const mp4ff_track_t * p_track = f->track[track];
+
+    if (p_track->stsz_sample_size)
+    {
+        bytes = p_track->stsz_sample_size;
+    } else {
+        bytes = p_track->stsz_table[sample];
+    }
+
+    return bytes;
+}
+
+int32_t mp4ff_set_sample_position(mp4ff_t *f, const int32_t track, const int32_t sample)
+{
+    int32_t offset;
+
+    offset = mp4ff_sample_to_offset(f, track, sample);
+    mp4ff_set_position(f, offset);
+
+    return 0;
+}

mp4ff/mp4util.c

+/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
+**
+** 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.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
+**
+** $Id: mp4util.c,v 1.15 2004/01/11 15:52:19 menno Exp $
+**/
+
+#include "mp4ffint.h"
+#include <stdlib.h>
+
+int32_t mp4ff_read_data(mp4ff_t *f, int8_t *data, uint32_t size)
+{
+    int32_t result = 1;
+
+    result = f->stream->read(f->stream->user_data, data, size);
+
+    f->current_position += size;
+
+    return result;
+}
+
+int32_t mp4ff_truncate(mp4ff_t * f)
+{
+	return f->stream->truncate(f->stream->user_data);
+}
+
+int32_t mp4ff_write_data(mp4ff_t *f, int8_t *data, uint32_t size)
+{
+    int32_t result = 1;
+
+    result = f->stream->write(f->stream->user_data, data, size);
+
+    f->current_position += size;
+
+    return result;
+}
+
+int32_t mp4ff_write_int32(mp4ff_t *f,const uint32_t data)
+{
+	uint32_t result;
+    uint32_t a, b, c, d;
+    int8_t temp[4];
+    
+    *(uint32_t*)temp = data;
+    a = (uint8_t)temp[0];
+    b = (uint8_t)temp[1];
+    c = (uint8_t)temp[2];
+    d = (uint8_t)temp[3];
+
+    result = (a<<24) | (b<<16) | (c<<8) | d;
+
+    return mp4ff_write_data(f,(uint8_t*)&result,sizeof(result));
+}
+
+int32_t mp4ff_set_position(mp4ff_t *f, const int64_t position)
+{
+    f->stream->seek(f->stream->user_data, position);
+    f->current_position = position;
+
+    return 0;
+}
+
+int64_t mp4ff_position(const mp4ff_t *f)
+{
+    return f->current_position;
+}
+
+uint64_t mp4ff_read_int64(mp4ff_t *f)
+{
+    uint8_t data[8];
+    uint64_t result = 0;
+    int8_t i;
+
+    mp4ff_read_data(f, data, 8);
+
+    for (i = 0; i < 8; i++)
+    {
+        result |= ((uint64_t)data[i]) << ((7 - i) * 8);
+    }
+
+    return result;
+}
+
+uint32_t mp4ff_read_int32(mp4ff_t *f)
+{
+    uint32_t result;
+    uint32_t a, b, c, d;
+    int8_t data[4];
+    
+    mp4ff_read_data(f, data, 4);
+    a = (uint8_t)data[0];
+    b = (uint8_t)data[1];
+    c = (uint8_t)data[2];
+    d = (uint8_t)data[3];
+
+    result = (a<<24) | (b<<16) | (c<<8) | d;
+    return (uint32_t)result;
+}
+
+uint32_t mp4ff_read_int24(mp4ff_t *f)
+{
+    uint32_t result;
+    uint32_t a, b, c;
+    int8_t data[4];
+    
+    mp4ff_read_data(f, data, 3);
+    a = (uint8_t)data[0];
+    b = (uint8_t)data[1];
+    c = (uint8_t)data[2];
+
+    result = (a<<16) | (b<<8) | c;
+    return (uint32_t)result;
+}
+
+uint16_t mp4ff_read_int16(mp4ff_t *f)
+{
+    uint32_t result;
+    uint32_t a, b;
+    int8_t data[2];
+    
+    mp4ff_read_data(f, data, 2);
+    a = (uint8_t)data[0];
+    b = (uint8_t)data[1];
+
+    result = (a<<8) | b;
+    return (uint16_t)result;
+}
+
+char * mp4ff_read_string(mp4ff_t * f,uint32_t length)
+{
+	char * str = (char*)malloc(length + 1);
+	if (str!=0)
+	{
+		if ((uint32_t)mp4ff_read_data(f,str,length)!=length)
+		{
+			free(str);
+			str = 0;
+		}
+		else
+		{
+			str[length] = 0;
+		}
+	}
+	return str;	
+}
+
+uint8_t mp4ff_read_char(mp4ff_t *f)
+{
+    uint8_t output;
+    mp4ff_read_data(f, &output, 1);
+    return output;
+}
+
+uint32_t mp4ff_read_mp4_descr_length(mp4ff_t *f)
+{
+    uint8_t b;
+    uint8_t numBytes = 0;
+    uint32_t length = 0;
+
+    do
+    {
+        b = mp4ff_read_char(f);
+        numBytes++;
+        length = (length << 7) | (b & 0x7F);
+    } while ((b & 0x80) && numBytes < 4);
+
+    return length;
+}