src/modules/audio_coding/main/source/audio_coding_module.cc

/*
 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


#include "acm_dtmf_detection.h"
#include "audio_coding_module.h"
#include "audio_coding_module_impl.h"
#include "trace.h"

namespace webrtc
{

// Create module
AudioCodingModule*
AudioCodingModule::Create(
    const WebRtc_Word32 id)
{
    return new AudioCodingModuleImpl(id);
}

// Destroy module
void
AudioCodingModule::Destroy(
        AudioCodingModule* module)
{
    delete static_cast<AudioCodingModuleImpl*> (module);
}

// Get number of supported codecs
WebRtc_UWord8 AudioCodingModule::NumberOfCodecs()
{
    WEBRTC_TRACE(webrtc::kTraceModuleCall, webrtc::kTraceAudioCoding, -1,
        "NumberOfCodecs()");
    return static_cast<WebRtc_UWord8>(ACMCodecDB::kNumCodecs);
}

// Get supported codec param with id
WebRtc_Word32
AudioCodingModule::Codec(
    const WebRtc_UWord8 listId,
    CodecInst&          codec)
{
    WEBRTC_TRACE(webrtc::kTraceModuleCall, webrtc::kTraceAudioCoding, -1,
        "Codec(const WebRtc_UWord8 listId, CodecInst& codec)");

    // Get the codec settings for the codec with the given list ID
    return ACMCodecDB::Codec(listId, &codec);
}

// Get supported codec Param with name
WebRtc_Word32
AudioCodingModule::Codec(
    const WebRtc_Word8* payloadName,
    CodecInst&          codec,
    const WebRtc_Word32 samplingFreqHz)
{
    WEBRTC_TRACE(webrtc::kTraceModuleCall, webrtc::kTraceAudioCoding, -1,
        "Codec(const WebRtc_Word8* payloadName, CodecInst& codec)");

    // Search through codec list for a matching name
    for(int codecCntr = 0; codecCntr < ACMCodecDB::kNumCodecs; codecCntr++)
    {
        // Store codec settings for codec number "codeCntr" in the output struct
        ACMCodecDB::Codec(codecCntr, &codec);

        if(!STR_CASE_CMP(codec.plname, payloadName))
        {
            // If samplingFreqHz is set (!= -1), check if frequency matches
            if((samplingFreqHz == codec.plfreq) || (samplingFreqHz == -1))
            {
                // We found a match, return OK
                return 0;
            }
        }
    }

    // if we are here we couldn't find anything
    // set the params to unacceptable values
    codec.plname[0] = '\0';
    codec.pltype    = -1;
    codec.pacsize   = 0;
    codec.rate      = 0;
    codec.plfreq    = 0;
    return -1;
}

// Get supported codec Index with name, and frequency if needed
WebRtc_Word32
AudioCodingModule::Codec(
    const WebRtc_Word8* payloadName,
    const WebRtc_Word32 samplingFreqHz)
{
    WEBRTC_TRACE(webrtc::kTraceModuleCall, webrtc::kTraceAudioCoding, -1,
        "Codec(const WebRtc_Word8* payloadName)");
    CodecInst codec;

    // Search through codec list for a matching name
    for(int codecCntr = 0; codecCntr < ACMCodecDB::kNumCodecs; codecCntr++)
    {
        // Temporally store codec settings for codec number "codeCntr" in "codec"
        ACMCodecDB::Codec(codecCntr, &codec);

        if(!STR_CASE_CMP(codec.plname, payloadName))
        {
            // If samplingFreqHz is set (!= -1), check if frequency matches
            if((samplingFreqHz == codec.plfreq) || (samplingFreqHz == -1))
            {
                // We found a match, return codec list number (index)
                return codecCntr;
            }
        }
    }

    // We did not find a matching codec in the list
    return -1;
}

// Checks the validity of the parameters of the given codec
bool
AudioCodingModule::IsCodecValid(
    const CodecInst& codec)
{
    int mirrorID;
    char errMsg[500];

    WEBRTC_TRACE(webrtc::kTraceModuleCall, webrtc::kTraceAudioCoding, -1,
               "IsCodecValid(const CodecInst& codec)");
    int codecNumber = ACMCodecDB::CodecNumber(&codec, &mirrorID, errMsg, 500);

    if(codecNumber < 0)
    {
        WEBRTC_TRACE(webrtc::kTraceError, webrtc::kTraceAudioCoding, -1, errMsg);
        return false;
    }
    else
    {
        return true;
    }
}

} // namespace webrtc