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Small refactor of AC3 encoder.
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It can now be initialised many times (not that it's ever used that way). Also let FFmpeg allocates the required memory automatically rather than using a fixed size buffer
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@jyavenard
jyavenard committed Jun 18, 2013
1 parent 7cd3a05 commit 3690ff3
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Showing 2 changed files with 38 additions and 59 deletions.
90 changes: 35 additions & 55 deletions mythtv/libs/libmyth/audio/audiooutputdigitalencoder.cpp
View file
Expand Up @@ -28,34 +28,22 @@ AudioOutputDigitalEncoder::AudioOutputDigitalEncoder(void) :
samples_per_frame(0),
m_spdifenc(NULL)
{
out = (outbuf_t *)av_malloc(OUTBUFSIZE);
out = (outbuf_t *)av_mallocz(OUTBUFSIZE);
if (out)
{
out_size = OUTBUFSIZE;
}
in = (inbuf_t *)av_malloc(INBUFSIZE);
in = (inbuf_t *)av_mallocz(INBUFSIZE);
if (in)
{
in_size = INBUFSIZE;
}
inp = (inbuf_t *)av_malloc(INBUFSIZE);

for (int i = 0; i < FF_MIN_BUFFER_SIZE; i++)
m_encodebuffer[i] = 0;
inp = (inbuf_t *)av_mallocz(INBUFSIZE);
}

AudioOutputDigitalEncoder::~AudioOutputDigitalEncoder()
{
Dispose();
}

void AudioOutputDigitalEncoder::Dispose()
{
if (av_context)
{
avcodec_close(av_context);
av_freep(&av_context);
}
Reset();
if (out)
{
av_freep(&out);
Expand All @@ -70,11 +58,19 @@ void AudioOutputDigitalEncoder::Dispose()
{
av_freep(&inp);
}
if (m_spdifenc)
}

void AudioOutputDigitalEncoder::Reset(void)
{
if (av_context)
{
delete m_spdifenc;
m_spdifenc = NULL;
avcodec_close(av_context);
av_freep(&av_context);
}
delete m_spdifenc;
m_spdifenc = NULL;

clear();
}

void *AudioOutputDigitalEncoder::realloc(void *ptr,
Expand Down Expand Up @@ -106,6 +102,15 @@ bool AudioOutputDigitalEncoder::Init(
.arg(ff_codec_id_string(codec_id)) .arg(bitrate)
.arg(samplerate) .arg(channels));

if (!(in || inp || out))
{
LOG(VB_GENERAL, LOG_ERR, LOC + "Memory allocation failed");
return false;
}

// Clear digital encoder from all existing content
Reset();

// We need to do this when called from mythmusic
avcodeclock->lock();
avcodec_register_all();
Expand All @@ -123,49 +128,22 @@ bool AudioOutputDigitalEncoder::Init(
av_context->bit_rate = bitrate;
av_context->sample_rate = samplerate;
av_context->channels = channels;
switch (channels)
{
case 1:
av_context->channel_layout = AV_CH_LAYOUT_MONO;
break;
case 2:
av_context->channel_layout = AV_CH_LAYOUT_STEREO;
break;
case 3:
av_context->channel_layout = AV_CH_LAYOUT_SURROUND;
break;
case 4:
av_context->channel_layout = AV_CH_LAYOUT_4POINT0;
break;
case 5:
av_context->channel_layout = AV_CH_LAYOUT_5POINT0;
break;
default:
av_context->channel_layout = AV_CH_LAYOUT_5POINT1;
break;
}
av_context->channel_layout = av_get_default_channel_layout(channels);
av_context->sample_fmt = AV_SAMPLE_FMT_S16P;

// open it
// open it
ret = avcodec_open2(av_context, codec, NULL);
if (ret < 0)
{
LOG(VB_GENERAL, LOG_ERR, LOC +
"Could not open codec, invalid bitrate or samplerate");

Dispose();
return false;
}

if (m_spdifenc)
{
delete m_spdifenc;
}

m_spdifenc = new SPDIFEncoder("spdif", AV_CODEC_ID_AC3);
if (!m_spdifenc->Succeeded())
{
Dispose();
LOG(VB_GENERAL, LOG_ERR, LOC + "Could not create spdif muxer");
return false;
}
Expand All @@ -188,8 +166,9 @@ size_t AudioOutputDigitalEncoder::Encode(void *buf, int len, AudioFormat format)
}

// Check if there is enough space in incoming buffer
int required_len = inlen + len / sampleSize *
AudioOutputSettings::SampleSize(FORMAT_S16);
int required_len = inlen +
len * AudioOutputSettings::SampleSize(FORMAT_S16) / sampleSize;

if (required_len > (int)in_size)
{
required_len = ((required_len / INBUFSIZE) + 1) * INBUFSIZE;
Expand Down Expand Up @@ -243,8 +222,8 @@ size_t AudioOutputDigitalEncoder::Encode(void *buf, int len, AudioFormat format)
{
AVPacket pkt;
av_init_packet(&pkt);
pkt.data = (uint8_t *)m_encodebuffer;
pkt.size = sizeof(m_encodebuffer);
pkt.data = NULL;
pkt.size = 0;
int got_packet = 0;

AudioOutputUtil::DeinterleaveSamples(
Expand All @@ -255,7 +234,6 @@ size_t AudioOutputDigitalEncoder::Encode(void *buf, int len, AudioFormat format)

int ret = avcodec_encode_audio2(av_context, &pkt, frame,
&got_packet);
int outsize = pkt.size;

if (ret < 0)
{
Expand All @@ -266,13 +244,15 @@ size_t AudioOutputDigitalEncoder::Encode(void *buf, int len, AudioFormat format)
i++;
if (!got_packet)
continue;
av_free_packet(&pkt);

if (!m_spdifenc)
{
m_spdifenc = new SPDIFEncoder("spdif", AV_CODEC_ID_AC3);
}
m_spdifenc->WriteFrame((uint8_t *)m_encodebuffer, outsize);

m_spdifenc->WriteFrame((uint8_t *)pkt.data, pkt.size);
av_free_packet(&pkt);

// Check if output buffer is big enough
required_len = outlen + m_spdifenc->GetProcessedSize();
if (required_len > (int)out_size)
Expand Down
7 changes: 3 additions & 4 deletions mythtv/libs/libmyth/audio/audiooutputdigitalencoder.h
View file
Expand Up @@ -21,15 +21,15 @@ class AudioOutputDigitalEncoder
~AudioOutputDigitalEncoder();

bool Init(CodecID codec_id, int bitrate, int samplerate, int channels);
void Dispose(void);
size_t Encode(void *buf, int len, AudioFormat format);
size_t GetFrames(void *ptr, int maxlen);
int Buffered(void) const
{ return inlen / sizeof(inbuf_t) / av_context->channels; }
void clear();
void clear();

private:
void *realloc(void *ptr, size_t old_size, size_t new_size);
void Reset(void);
void *realloc(void *ptr, size_t old_size, size_t new_size);

AVCodecContext *av_context;
outbuf_t *out;
Expand All @@ -39,7 +39,6 @@ class AudioOutputDigitalEncoder
int outlen;
int inlen;
size_t samples_per_frame;
int16_t m_encodebuffer[FF_MIN_BUFFER_SIZE];
SPDIFEncoder *m_spdifenc;
};

Expand Down

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