Renesas / Mbed OS GR-PEACH_Audio_Playback_Sample

The "GR-PEACH_Audio_Playback_Sample" is a sample code that can provides high-resolution audio playback of FLAC format files. It also allows the user to audio-playback control functions such as play, pause, and stop by manipulating key switches.

Dependencies:   R_BSP TLV320_RBSP USBHost_custom

Note

For a sample program of with LCD Board,
please refer to GR-PEACH_Audio_Playback_7InchLCD_Sample.

Introduction

The "GR-PEACH_Audio_Playback_Sample" is a sample code that can provides high-resolution audio playback of FLAC format files. It also allows the user to audio-playback control functions such as play, pause, and stop by manipulating key switches.

1. Overview of the Sample Code

1.1 Software Block Diagram

Figure 1.1 shows the software block diagram.

/media/uploads/dkato/audioplayback_figure1_1x.png

1.2 Pin Definitions

Table 1.1 shows the pins that this sample code are to use.

/media/uploads/dkato/audioplayback_table1_1.png

2. Sample Code Operating Environment

This sample code runs in GR-PEACH + the Audio/Camera shield for the GR-PEACH environment. This section explains the functions of the ports that are used by this sample code.

2.1 Operating Environment

Figure 2.1 shows the configuration of the operating environment for running this sample code.

/media/uploads/dkato/audioplayback_figure2_1.png /media/uploads/1050186/figure2_2.png /media/uploads/dkato/audioplayback_figure2_3.png

2.2 List of User Operations

A list of user operations on the command line, TFT touch keys, and switch key that the user can perform for this sample code is shown in. Table 2.1.

/media/uploads/dkato/audioplayback_table2_1x.png

3. Function Outline

The functions of this sample code are summarized in Table 3.1 to Table 3.3.

/media/uploads/dkato/audioplayback_table3_1.png /media/uploads/dkato/audioplayback_table3_2.png /media/uploads/dkato/audioplayback_table3_3.png /media/uploads/dkato/audioplayback_figure3_1.png

3.1 Playback Control

The playback control that the sample code supports include play, pause, stop, skip to next, and skip to previous.

3.2 Trick Play Control

Manipulating "Repeat" alternates between "Repeat mode On" and "Repeat mode Off". The default mode is "Repeat mode On". When the repeat mode is on, the playback of the first song starts after the playback of the last song is finished. When the repeat mode is off, the sample code enters the stopped state after the playback of the last song is finished.

3.3 Acquisition of the Song Information

The information of the song being played is obtained by operating the "Play info" during the playback of the song. Table 3.4 lists the items of information that can be obtained by the "Play info" operation.

/media/uploads/dkato/audioplayback_table3_4.png

3.4 How the Folder Structure is Analyzed

The sample coded analyzes the folder structure in the breadth-first search order. The order in which files are numbered is illustrated in Table 3.5. The sample code does not sort the files by file or folder name.

/media/uploads/dkato/audioplayback_table3_5.png

4.Others

The default setting of serial communication (baud rate etc.) in mbed is shown the following link.
Please refer to the link and change the settings of your PC terminal software.
The default value of baud rate in mbed is 9600, and this application uses baud rate 9600.
https://developer.mbed.org/teams/Renesas/wiki/GR-PEACH-Getting-Started#install-the-usb-serial-communication

flac/AUTHORS

Committer:
Osamu Nakamura
Date:
2017-03-31
Revision:
6:df19c3e787ca
Parent:
0:ee40da884cfc

File content as of revision 6:df19c3e787ca:

/* FLAC - Free Lossless Audio Codec
 * Copyright (C) 2001-2009  Josh Coalson
 * Copyright (C) 2011-2014  Xiph.Org Foundation
 *
 * This file is part the FLAC project.  FLAC is comprised of several
 * components distributed under different licenses.  The codec libraries
 * are distributed under Xiph.Org's BSD-like license (see the file
 * COPYING.Xiph in this distribution).  All other programs, libraries, and
 * plugins are distributed under the GPL (see COPYING.GPL).  The documentation
 * is distributed under the Gnu FDL (see COPYING.FDL).  Each file in the
 * FLAC distribution contains at the top the terms under which it may be
 * distributed.
 *
 * Since this particular file is relevant to all components of FLAC,
 * it may be distributed under the Xiph.Org license, which is the least
 * restrictive of those mentioned above.  See the file COPYING.Xiph in this
 * distribution.
 */

Current FLAC maintainer: Erik de Castro Lopo <erikd@mega-nerd.com>

Original author: Josh Coalson <jcoalson@users.sourceforge.net>

Website : https://www.xiph.org/flac/

FLAC is an Open Source lossless audio codec originally developed by Josh Coalson
between 2001 and 2009. From 2009 to 2012 FLAC was basically unmaintained. In
2012 the Erik de Castro Lopo became the chief maintainer as part of the
Xiph.Org Foundation.

Other major contributors and their contributions:

"lvqcl" <lvqcl@users.sourceforge.net>
* Visual Studio build system.
* Optimisations in the encoder and decoder.

"Janne Hyvärinen" <cse@sci.fi>
* Visual Studio build system.
* Unicode handling on Windows.

"Andrey Astafiev" <andrei@tvcell.ru>
* Russian translation of the HTML documentation

"Miroslav Lichvar" <lichvarm@phoenix.inf.upol.cz>
* IA-32 assembly versions of several libFLAC routines

"Brady Patterson" <bpat@users.sourceforge.net>
* AIFF file support, PPC assembly versions of libFLAC routines

"Daisuke Shimamura" <Daisuke_Shimamura@nifty.com>
* i18n support in the XMMS plugin

"X-Fixer" <x-fixer@narod.ru>
* Configuration system, tag editing, and file info in the Winamp2 plugin

"Matt Zimmerman" <mdz@debian.org>
* Libtool/autoconf/automake make system, flac man page