AUD_FFMPEGWriter.cpp

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/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * Copyright 2009-2011 Jörg Hermann Müller
 *
 * This file is part of AudaSpace.
 *
 * Audaspace 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.
 *
 * AudaSpace 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 Audaspace; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

// needed for INT64_C
#ifndef __STDC_CONSTANT_MACROS
#define __STDC_CONSTANT_MACROS
#endif

#include "AUD_FFMPEGWriter.h"

extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavformat/avio.h>
#include "ffmpeg_compat.h"
}

static const char* context_error = "AUD_FFMPEGWriter: Couldn't allocate context.";
static const char* codec_error = "AUD_FFMPEGWriter: Invalid codec or codec not found.";
static const char* stream_error = "AUD_FFMPEGWriter: Couldn't allocate stream.";
static const char* format_error = "AUD_FFMPEGWriter: Unsupported sample format.";
static const char* file_error = "AUD_FFMPEGWriter: File couldn't be written.";
static const char* write_error = "AUD_FFMPEGWriter: Error writing packet.";

AUD_FFMPEGWriter::AUD_FFMPEGWriter(std::string filename, AUD_DeviceSpecs specs, AUD_Container format, AUD_Codec codec, unsigned int bitrate) :
    m_position(0),
    m_specs(specs),
    m_input_samples(0)
{
    static const char* formats[] = { NULL, "ac3", "flac", "matroska", "mp2", "mp3", "ogg", "wav" };

    if(avformat_alloc_output_context2(&m_formatCtx, NULL, formats[format], filename.c_str()))
        AUD_THROW(AUD_ERROR_FFMPEG, context_error);

    m_outputFmt = m_formatCtx->oformat;

    switch(codec)
    {
    case AUD_CODEC_AAC:
        m_outputFmt->audio_codec = CODEC_ID_AAC;
        break;
    case AUD_CODEC_AC3:
        m_outputFmt->audio_codec = CODEC_ID_AC3;
        break;
    case AUD_CODEC_FLAC:
        m_outputFmt->audio_codec = CODEC_ID_FLAC;
        break;
    case AUD_CODEC_MP2:
        m_outputFmt->audio_codec = CODEC_ID_MP2;
        break;
    case AUD_CODEC_MP3:
        m_outputFmt->audio_codec = CODEC_ID_MP3;
        break;
    case AUD_CODEC_PCM:
        switch(specs.format)
        {
        case AUD_FORMAT_U8:
            m_outputFmt->audio_codec = CODEC_ID_PCM_U8;
            break;
        case AUD_FORMAT_S16:
            m_outputFmt->audio_codec = CODEC_ID_PCM_S16LE;
            break;
        case AUD_FORMAT_S24:
            m_outputFmt->audio_codec = CODEC_ID_PCM_S24LE;
            break;
        case AUD_FORMAT_S32:
            m_outputFmt->audio_codec = CODEC_ID_PCM_S32LE;
            break;
        case AUD_FORMAT_FLOAT32:
            m_outputFmt->audio_codec = CODEC_ID_PCM_F32LE;
            break;
        case AUD_FORMAT_FLOAT64:
            m_outputFmt->audio_codec = CODEC_ID_PCM_F64LE;
            break;
        default:
            m_outputFmt->audio_codec = CODEC_ID_NONE;
            break;
        }
        break;
    case AUD_CODEC_VORBIS:
        m_outputFmt->audio_codec = CODEC_ID_VORBIS;
        break;
    default:
        m_outputFmt->audio_codec = CODEC_ID_NONE;
        break;
    }

    try
    {
        if(m_outputFmt->audio_codec == CODEC_ID_NONE)
            AUD_THROW(AUD_ERROR_SPECS, codec_error);

        m_stream = av_new_stream(m_formatCtx, 0);
        if(!m_stream)
            AUD_THROW(AUD_ERROR_FFMPEG, stream_error);

        m_codecCtx = m_stream->codec;
        m_codecCtx->codec_id = m_outputFmt->audio_codec;
        m_codecCtx->codec_type = AVMEDIA_TYPE_AUDIO;
        m_codecCtx->bit_rate = bitrate;
        m_codecCtx->sample_rate = int(m_specs.rate);
        m_codecCtx->channels = m_specs.channels;
        m_codecCtx->time_base.num = 1;
        m_codecCtx->time_base.den = m_codecCtx->sample_rate;

        switch(m_specs.format)
        {
        case AUD_FORMAT_U8:
            m_convert = AUD_convert_float_u8;
            m_codecCtx->sample_fmt = SAMPLE_FMT_U8;
            break;
        case AUD_FORMAT_S16:
            m_convert = AUD_convert_float_s16;
            m_codecCtx->sample_fmt = SAMPLE_FMT_S16;
            break;
        case AUD_FORMAT_S32:
            m_convert = AUD_convert_float_s32;
            m_codecCtx->sample_fmt = SAMPLE_FMT_S32;
            break;
        case AUD_FORMAT_FLOAT32:
            m_convert = AUD_convert_copy<float>;
            m_codecCtx->sample_fmt = SAMPLE_FMT_FLT;
            break;
        case AUD_FORMAT_FLOAT64:
            m_convert = AUD_convert_float_double;
            m_codecCtx->sample_fmt = SAMPLE_FMT_DBL;
            break;
        default:
            AUD_THROW(AUD_ERROR_FFMPEG, format_error);
        }

        try
        {
            if(m_formatCtx->oformat->flags & AVFMT_GLOBALHEADER)
                m_codecCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;

            AVCodec* codec = avcodec_find_encoder(m_codecCtx->codec_id);
            if(!codec)
                AUD_THROW(AUD_ERROR_FFMPEG, codec_error);

            if(avcodec_open(m_codecCtx, codec))
                AUD_THROW(AUD_ERROR_FFMPEG, codec_error);

            m_output_buffer.resize(FF_MIN_BUFFER_SIZE);
            int samplesize = AUD_MAX(AUD_SAMPLE_SIZE(m_specs), AUD_DEVICE_SAMPLE_SIZE(m_specs));

            if(m_codecCtx->frame_size <= 1)
                m_input_size = 0;
            else
            {
                m_input_buffer.resize(m_codecCtx->frame_size * samplesize);
                m_input_size = m_codecCtx->frame_size;
            }

            try
            {
                if(avio_open(&m_formatCtx->pb, filename.c_str(), AVIO_FLAG_WRITE))
                    AUD_THROW(AUD_ERROR_FILE, file_error);

                avformat_write_header(m_formatCtx, NULL);
            }
            catch(AUD_Exception&)
            {
                avcodec_close(m_codecCtx);
                av_freep(&m_formatCtx->streams[0]->codec);
                throw;
            }
        }
        catch(AUD_Exception&)
        {
            av_freep(&m_formatCtx->streams[0]);
            throw;
        }
    }
    catch(AUD_Exception&)
    {
        av_free(m_formatCtx);
        throw;
    }
}

AUD_FFMPEGWriter::~AUD_FFMPEGWriter()
{
    // writte missing data
    if(m_input_samples)
    {
        sample_t* buf = m_input_buffer.getBuffer();
        memset(buf + m_specs.channels * m_input_samples, 0,
               (m_input_size - m_input_samples) * AUD_DEVICE_SAMPLE_SIZE(m_specs));

        encode(buf);
    }

    av_write_trailer(m_formatCtx);

    avcodec_close(m_codecCtx);

    av_freep(&m_formatCtx->streams[0]->codec);
    av_freep(&m_formatCtx->streams[0]);

    avio_close(m_formatCtx->pb);
    av_free(m_formatCtx);
}

int AUD_FFMPEGWriter::getPosition() const
{
    return m_position;
}

AUD_DeviceSpecs AUD_FFMPEGWriter::getSpecs() const
{
    return m_specs;
}

void AUD_FFMPEGWriter::encode(sample_t* data)
{
    sample_t* outbuf = m_output_buffer.getBuffer();

    // convert first
    if(m_input_size)
        m_convert(reinterpret_cast<data_t*>(data), reinterpret_cast<data_t*>(data), m_input_size * m_specs.channels);

    AVPacket packet;
    av_init_packet(&packet);
    packet.size = avcodec_encode_audio(m_codecCtx, reinterpret_cast<uint8_t*>(outbuf), m_output_buffer.getSize(), reinterpret_cast<short*>(data));
    if(m_codecCtx->coded_frame && m_codecCtx->coded_frame->pts != AV_NOPTS_VALUE)
        packet.pts = av_rescale_q(m_codecCtx->coded_frame->pts, m_codecCtx->time_base, m_stream->time_base);
    packet.flags |= AV_PKT_FLAG_KEY;
    packet.stream_index = m_stream->index;
    packet.data = reinterpret_cast<uint8_t*>(outbuf);

    if(av_interleaved_write_frame(m_formatCtx, &packet))
        AUD_THROW(AUD_ERROR_FFMPEG, write_error);
}

void AUD_FFMPEGWriter::write(unsigned int length, sample_t* buffer)
{
    unsigned int samplesize = AUD_SAMPLE_SIZE(m_specs);

    if(m_input_size)
    {
        sample_t* inbuf = m_input_buffer.getBuffer();

        while(length)
        {
            unsigned int len = AUD_MIN(m_input_size - m_input_samples, length);

            memcpy(inbuf + m_input_samples * m_specs.channels, buffer, len * samplesize);

            buffer += len * m_specs.channels;
            m_input_samples += len;
            m_position += len;
            length -= len;

            if(m_input_samples == m_input_size)
            {
                encode(inbuf);

                m_input_samples = 0;
            }
        }
    }
    else // PCM data, can write directly!
    {
        int samplesize = AUD_SAMPLE_SIZE(m_specs);
        if(m_output_buffer.getSize() != length * m_specs.channels * m_codecCtx->bits_per_coded_sample / 8)
            m_output_buffer.resize(length * m_specs.channels * m_codecCtx->bits_per_coded_sample / 8);
        m_input_buffer.assureSize(length * AUD_MAX(AUD_DEVICE_SAMPLE_SIZE(m_specs), samplesize));

        sample_t* buf = m_input_buffer.getBuffer();
        m_convert(reinterpret_cast<data_t*>(buf), reinterpret_cast<data_t*>(buffer), length * m_specs.channels);

        encode(buf);

        m_position += length;
    }
}