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Differential D2716 Diff 9135 extern/audaspace/plugins/ffmpeg/FFMPEGReader.cpp

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extern/audaspace/plugins/ffmpeg/FFMPEGReader.cpp

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/*******************************************************************************
* Copyright 2009-2016 Jörg Müller
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
#include "FFMPEGReader.h"
#include "Exception.h"
#include <algorithm>
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avio.h>
}
AUD_NAMESPACE_BEGIN
int FFMPEGReader::decode(AVPacket& packet, Buffer& buffer)
{
AVFrame* frame = nullptr;
int got_frame;
int read_length;
uint8_t* orig_data = packet.data;
int orig_size = packet.size;
int buf_size = buffer.getSize();
int buf_pos = 0;
while(packet.size > 0)
{
got_frame = 0;
if(!frame)
frame = av_frame_alloc();
else
av_frame_unref(frame);
read_length = avcodec_decode_audio4(m_codecCtx, frame, &got_frame, &packet);
if(read_length < 0)
break;
if(got_frame)
{
int data_size = av_samples_get_buffer_size(nullptr, m_codecCtx->channels, frame->nb_samples, m_codecCtx->sample_fmt, 1);
if(buf_size - buf_pos < data_size)
{
buffer.resize(buf_size + data_size, true);
buf_size += data_size;
}
if(m_tointerleave)
{
int single_size = data_size / m_codecCtx->channels / frame->nb_samples;
for(int channel = 0; channel < m_codecCtx->channels; channel++)
{
for(int i = 0; i < frame->nb_samples; i++)
{
std::memcpy(((data_t*)buffer.getBuffer()) + buf_pos + ((m_codecCtx->channels * i) + channel) * single_size,
frame->data[channel] + i * single_size, single_size);
}
}
}
else
std::memcpy(((data_t*)buffer.getBuffer()) + buf_pos, frame->data[0], data_size);
buf_pos += data_size;
}
packet.size -= read_length;
packet.data += read_length;
}
packet.data = orig_data;
packet.size = orig_size;
av_free(frame);
return buf_pos;
}
void FFMPEGReader::init()
{
m_position = 0;
m_pkgbuf_left = 0;
if(avformat_find_stream_info(m_formatCtx, nullptr) < 0)
AUD_THROW(FileException, "File couldn't be read, ffmpeg couldn't find the stream info.");
// find audio stream and codec
m_stream = -1;
for(unsigned int i = 0; i < m_formatCtx->nb_streams; i++)
{
if((m_formatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_AUDIO)
&& (m_stream < 0))
{
m_stream=i;
break;
}
}
if(m_stream == -1)
AUD_THROW(FileException, "File couldn't be read, no audio stream found by ffmpeg.");
m_codecCtx = m_formatCtx->streams[m_stream]->codec;
// get a decoder and open it
AVCodec* aCodec = avcodec_find_decoder(m_codecCtx->codec_id);
if(!aCodec)
AUD_THROW(FileException, "File couldn't be read, no decoder found with ffmpeg.");
if(avcodec_open2(m_codecCtx, aCodec, nullptr) < 0)
AUD_THROW(FileException, "File couldn't be read, ffmpeg codec couldn't be opened.");
m_specs.channels = (Channels) m_codecCtx->channels;
m_tointerleave = av_sample_fmt_is_planar(m_codecCtx->sample_fmt);
switch(av_get_packed_sample_fmt(m_codecCtx->sample_fmt))
{
case AV_SAMPLE_FMT_U8:
m_convert = convert_u8_float;
m_specs.format = FORMAT_U8;
break;
case AV_SAMPLE_FMT_S16:
m_convert = convert_s16_float;
m_specs.format = FORMAT_S16;
break;
case AV_SAMPLE_FMT_S32:
m_convert = convert_s32_float;
m_specs.format = FORMAT_S32;
break;
case AV_SAMPLE_FMT_FLT:
m_convert = convert_copy<float>;
m_specs.format = FORMAT_FLOAT32;
break;
case AV_SAMPLE_FMT_DBL:
m_convert = convert_double_float;
m_specs.format = FORMAT_FLOAT64;
break;
default:
AUD_THROW(FileException, "File couldn't be read, ffmpeg sample format unknown.");
}
m_specs.rate = (SampleRate) m_codecCtx->sample_rate;
}
FFMPEGReader::FFMPEGReader(std::string filename) :
m_pkgbuf(),
m_formatCtx(nullptr),
m_aviocontext(nullptr),
m_membuf(nullptr)
{
// open file
if(avformat_open_input(&m_formatCtx, filename.c_str(), nullptr, nullptr)!=0)
AUD_THROW(FileException, "File couldn't be opened with ffmpeg.");
try
{
init();
}
catch(Exception&)
{
avformat_close_input(&m_formatCtx);
throw;
}
}
FFMPEGReader::FFMPEGReader(std::shared_ptr<Buffer> buffer) :
m_pkgbuf(),
m_membuffer(buffer),
m_membufferpos(0)
{
m_membuf = reinterpret_cast<data_t*>(av_malloc(FF_MIN_BUFFER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE));
m_aviocontext = avio_alloc_context(m_membuf, FF_MIN_BUFFER_SIZE, 0, this, read_packet, nullptr, seek_packet);
if(!m_aviocontext)
{
av_free(m_aviocontext);
AUD_THROW(FileException, "Buffer reading context couldn't be created with ffmpeg.");
}
m_formatCtx = avformat_alloc_context();
m_formatCtx->pb = m_aviocontext;
if(avformat_open_input(&m_formatCtx, "", nullptr, nullptr)!=0)
{
av_free(m_aviocontext);
AUD_THROW(FileException, "Buffer couldn't be read with ffmpeg.");
}
try
{
init();
}
catch(Exception&)
{
avformat_close_input(&m_formatCtx);
av_free(m_aviocontext);
throw;
}
}
FFMPEGReader::~FFMPEGReader()
{
avcodec_close(m_codecCtx);
avformat_close_input(&m_formatCtx);
}
int FFMPEGReader::read_packet(void* opaque, uint8_t* buf, int buf_size)
{
FFMPEGReader* reader = reinterpret_cast<FFMPEGReader*>(opaque);
int size = std::min(buf_size, int(reader->m_membuffer->getSize() - reader->m_membufferpos));
if(size < 0)
return -1;
std::memcpy(buf, ((data_t*)reader->m_membuffer->getBuffer()) + reader->m_membufferpos, size);
reader->m_membufferpos += size;
return size;
}
int64_t FFMPEGReader::seek_packet(void* opaque, int64_t offset, int whence)
{
FFMPEGReader* reader = reinterpret_cast<FFMPEGReader*>(opaque);
switch(whence)
{
case SEEK_SET:
reader->m_membufferpos = 0;
break;
case SEEK_END:
reader->m_membufferpos = reader->m_membuffer->getSize();
break;
case AVSEEK_SIZE:
return reader->m_membuffer->getSize();
}
return (reader->m_membufferpos += offset);
}
bool FFMPEGReader::isSeekable() const
{
return true;
}
void FFMPEGReader::seek(int position)
{
if(position >= 0)
{
uint64_t st_time = m_formatCtx->start_time;
uint64_t seek_pos = ((uint64_t)position) * ((uint64_t)AV_TIME_BASE) / ((uint64_t)m_specs.rate);
if(st_time != AV_NOPTS_VALUE) {
seek_pos += st_time;
}
double pts_time_base =
av_q2d(m_formatCtx->streams[m_stream]->time_base);
uint64_t pts_st_time =
((st_time != AV_NOPTS_VALUE) ? st_time : 0)
/ pts_time_base / (uint64_t) AV_TIME_BASE;
// a value < 0 tells us that seeking failed
if(av_seek_frame(m_formatCtx, -1, seek_pos,
AVSEEK_FLAG_BACKWARD | AVSEEK_FLAG_ANY) >= 0)
{
avcodec_flush_buffers(m_codecCtx);
m_position = position;
AVPacket packet;
bool search = true;
while(search && av_read_frame(m_formatCtx, &packet) >= 0)
{
// is it a frame from the audio stream?
if(packet.stream_index == m_stream)
{
// decode the package
m_pkgbuf_left = decode(packet, m_pkgbuf);
search = false;
// check position
if(packet.pts != AV_NOPTS_VALUE)
{
// calculate real position, and read to frame!
m_position = (packet.pts - pts_st_time) * pts_time_base * m_specs.rate;
if(m_position < position)
{
// read until we're at the right position
int length = AUD_DEFAULT_BUFFER_SIZE;
Buffer buffer(length * AUD_SAMPLE_SIZE(m_specs));
bool eos;
for(int len = position - m_position; len > 0; len -= AUD_DEFAULT_BUFFER_SIZE)
{
if(len < AUD_DEFAULT_BUFFER_SIZE)
length = len;
read(length, eos, buffer.getBuffer());
}
}
}
}
av_free_packet(&packet);
}
}
else
{
fprintf(stderr, "seeking failed!\n");
// Seeking failed, do nothing.
}
}
}
int FFMPEGReader::getLength() const
{
// return approximated remaning size
return (int)((m_formatCtx->duration * m_codecCtx->sample_rate)
/ AV_TIME_BASE)-m_position;
}
int FFMPEGReader::getPosition() const
{
return m_position;
}
Specs FFMPEGReader::getSpecs() const
{
return m_specs.specs;
}
void FFMPEGReader::read(int& length, bool& eos, sample_t* buffer)
{
// read packages and decode them
AVPacket packet;
int data_size = 0;
int pkgbuf_pos;
int left = length;
int sample_size = AUD_DEVICE_SAMPLE_SIZE(m_specs);
sample_t* buf = buffer;
pkgbuf_pos = m_pkgbuf_left;
m_pkgbuf_left = 0;
// there may still be data in the buffer from the last call
if(pkgbuf_pos > 0)
{
data_size = std::min(pkgbuf_pos, left * sample_size);
m_convert((data_t*) buf, (data_t*) m_pkgbuf.getBuffer(), data_size / AUD_FORMAT_SIZE(m_specs.format));
buf += data_size / AUD_FORMAT_SIZE(m_specs.format);
left -= data_size/sample_size;
}
// for each frame read as long as there isn't enough data already
while((left > 0) && (av_read_frame(m_formatCtx, &packet) >= 0))
{
// is it a frame from the audio stream?
if(packet.stream_index == m_stream)
{
// decode the package
pkgbuf_pos = decode(packet, m_pkgbuf);
// copy to output buffer
data_size = std::min(pkgbuf_pos, left * sample_size);
m_convert((data_t*) buf, (data_t*) m_pkgbuf.getBuffer(), data_size / AUD_FORMAT_SIZE(m_specs.format));
buf += data_size / AUD_FORMAT_SIZE(m_specs.format);
left -= data_size/sample_size;
}
av_free_packet(&packet);
}
// read more data than necessary?
if(pkgbuf_pos > data_size)
{
m_pkgbuf_left = pkgbuf_pos-data_size;
memmove(m_pkgbuf.getBuffer(),
((data_t*)m_pkgbuf.getBuffer())+data_size,
pkgbuf_pos-data_size);
}
if((eos = (left > 0)))
length -= left;
m_position += length;
}
AUD_NAMESPACE_END