virtual bool GetVideoInformation(unsigned int &width, unsigned int &height) override
{
if (pictureId == pictureIdPrev)
return false;
pictureIdPrev = pictureId;
if (AP4_AvcSampleDescription *avc = AP4_DYNAMIC_CAST(AP4_AvcSampleDescription, sample_description))
{
AP4_Array<AP4_DataBuffer>& buffer = avc->GetPictureParameters();
AP4_AvcPictureParameterSet pps;
for (unsigned int i(0); i < buffer.ItemCount(); ++i)
{
if (AP4_SUCCEEDED(AP4_AvcFrameParser::ParsePPS(buffer[i].GetData(), buffer[i].GetDataSize(), pps)) && pps.pic_parameter_set_id == pictureId)
{
buffer = avc->GetSequenceParameters();
AP4_AvcSequenceParameterSet sps;
for (unsigned int i(0); i < buffer.ItemCount(); ++i)
{
if (AP4_SUCCEEDED(AP4_AvcFrameParser::ParseSPS(buffer[i].GetData(), buffer[i].GetDataSize(), sps)) && sps.seq_parameter_set_id == pps.seq_parameter_set_id)
{
sps.GetInfo(width, height);
return true;
}
}
break;
}
}
}
return false;
};
int8_t Mp4Writer::WriteFile(int frameRate)
{
// frameRate should be in frames/second
// adjust the sample CTS/DTS offsets based on the sample orders
if (m_sample_orders.ItemCount() > 1) {
unsigned int start = 0;
for (unsigned int i=1; i<=m_sample_orders.ItemCount(); i++) {
if (i == m_sample_orders.ItemCount() || m_sample_orders[i].m_DisplayOrder == 0) {
// we got to the end of the GOP, sort it by display order
mp_sample_storage->SortSamples(&m_sample_orders[start], i-start);
start = i;
}
}
}
unsigned int max_delta = 0;
for (unsigned int i=0; i<m_sample_orders.ItemCount(); i++) {
if (m_sample_orders[i].m_DecodeOrder > i) {
unsigned int delta =m_sample_orders[i].m_DecodeOrder-i;
if (delta > max_delta) {
max_delta = delta;
}
}
}
for (unsigned int i=0; i<m_sample_orders.ItemCount(); i++) {
mp_sample_table->UseSample(m_sample_orders[i].m_DecodeOrder).SetCts(1000ULL*(AP4_UI64)(i+max_delta));
}
// check the video parameters
AP4_AvcSequenceParameterSet* sps = NULL;
for (unsigned int i=0; i<=AP4_AVC_SPS_MAX_ID; i++) {
if (m_parser.GetSequenceParameterSets()[i]) {
sps = m_parser.GetSequenceParameterSets()[i];
break;
}
}
if (sps == NULL) {
m_errorMsg = "ERROR: no sequence parameter set found in video";
return -1;
}
unsigned int video_width = 0;
unsigned int video_height = 0;
sps->GetInfo(video_width, video_height);
// collect the SPS and PPS into arrays
AP4_Array<AP4_DataBuffer> sps_array;
for (unsigned int i=0; i<=AP4_AVC_SPS_MAX_ID; i++) {
if (m_parser.GetSequenceParameterSets()[i]) {
sps_array.Append(m_parser.GetSequenceParameterSets()[i]->raw_bytes);
}
}
AP4_Array<AP4_DataBuffer> pps_array;
for (unsigned int i=0; i<=AP4_AVC_PPS_MAX_ID; i++) {
if (m_parser.GetPictureParameterSets()[i]) {
pps_array.Append(m_parser.GetPictureParameterSets()[i]->raw_bytes);
}
}
// setup the video the sample descripton
AP4_AvcSampleDescription* sample_description =
new AP4_AvcSampleDescription(AP4_SAMPLE_FORMAT_AVC1,
video_width,
video_height,
24,
"h264",
sps->profile_idc,
sps->level_idc,
sps->constraint_set0_flag<<7 |
sps->constraint_set1_flag<<6 |
sps->constraint_set2_flag<<5 |
sps->constraint_set3_flag<<4,
4,
sps_array,
pps_array);
mp_sample_table->AddSampleDescription(sample_description);
// TODO: set frame rate here
m_frameRate = frameRate * 1000;
AP4_UI32 movie_timescale = 1000;
AP4_UI32 media_timescale = m_frameRate;
AP4_UI64 video_track_duration = AP4_ConvertTime(1000*mp_sample_table->GetSampleCount(), media_timescale, movie_timescale);
AP4_UI64 video_media_duration = 1000*mp_sample_table->GetSampleCount();
// create a video track
AP4_Track* track = new AP4_Track(AP4_Track::TYPE_VIDEO,
mp_sample_table,
0, // auto-select track id
movie_timescale, // movie time scale
video_track_duration, // track duration
m_frameRate, // media time scale
video_media_duration, // media duration
"und", // language
video_width<<16, // width
video_height<<16 // height
);
// update the brands list
m_brands.Append(AP4_FILE_BRAND_AVC1);
mp_movie->AddTrack(track);
// open the output
AP4_Result result;
AP4_ByteStream* output = NULL;
result = AP4_FileByteStream::Create(m_outputFilename.c_str(),
AP4_FileByteStream::STREAM_MODE_WRITE, output);
if (AP4_FAILED(result)) {
m_errorMsg = "ERROR: cannot open output file";
return -1;
}
// create a multimedia file
AP4_File file(mp_movie);
// set the file type
file.SetFileType(AP4_FILE_BRAND_MP42, 1, &m_brands[0], m_brands.ItemCount());
// write the file to the output
AP4_FileWriter::Write(file, *output);
// cleanup
output->Release();
}
