Add DHT data to MJPEG source images if not present.

This commit is contained in:
Peter Johnson
2016-11-02 21:32:13 -07:00
parent 7067179b28
commit 46085824ae

View File

@@ -16,6 +16,44 @@ using namespace cs;
static constexpr std::size_t kMaxFramesAvail = 32;
// DHT data for MJPEG images that don't have it.
static const unsigned char dhtData[] = {
0xff, 0xc4, 0x01, 0xa2, 0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01,
0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02,
0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x01, 0x00, 0x03,
0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
0x0a, 0x0b, 0x10, 0x00, 0x02, 0x01, 0x03, 0x03, 0x02, 0x04, 0x03, 0x05,
0x05, 0x04, 0x04, 0x00, 0x00, 0x01, 0x7d, 0x01, 0x02, 0x03, 0x00, 0x04,
0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22,
0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1, 0x15,
0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, 0x17,
0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36,
0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66,
0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95,
0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8,
0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2,
0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5,
0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9,
0xfa, 0x11, 0x00, 0x02, 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05,
0x04, 0x04, 0x00, 0x01, 0x02, 0x77, 0x00, 0x01, 0x02, 0x03, 0x11, 0x04,
0x05, 0x21, 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33,
0x52, 0xf0, 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25,
0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36,
0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66,
0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94,
0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
0xe8, 0xe9, 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa};
SourceImpl::SourceImpl(llvm::StringRef name)
: m_name{name}, m_frame{*this, nullptr} {}
@@ -253,6 +291,29 @@ std::vector<VideoMode> SourceImpl::EnumerateVideoModes(
void SourceImpl::PutFrame(VideoMode::PixelFormat pixelFormat,
llvm::StringRef data, Frame::Time time) {
std::size_t dataSize = data.size();
// If MJPEG, determine if we need to add DHT to it, and allocate enough space
// for adding it if required.
bool addDHT = false;
std::size_t locSOF = dataSize;
if (pixelFormat == VideoMode::kMJPEG) {
// Search first 2048 bytes (or until SOS) for DHT tag
for (llvm::StringRef::size_type i = 0; i < 2048 && i < data.size(); ++i) {
if (static_cast<unsigned char>(data[i]) != 0xff) continue; // not a tag
unsigned char tag = static_cast<unsigned char>(data[i + 1]);
if (tag == 0xda) break; // SOS
if (tag == 0xc4) goto done; // DHT
if (tag == 0xc0) locSOF = i; // SOF
}
// Only add DHT if we also found SOF (insertion point)
if (locSOF != dataSize) {
addDHT = true;
dataSize += sizeof(dhtData);
}
}
done:
std::unique_ptr<Frame::Data> frameData;
{
std::lock_guard<std::mutex> lock{m_poolMutex};
@@ -260,7 +321,7 @@ void SourceImpl::PutFrame(VideoMode::PixelFormat pixelFormat,
int found = -1;
for (std::size_t i = 0; i < m_framesAvail.size(); ++i) {
// is it big enough?
if (m_framesAvail[i] && m_framesAvail[i]->capacity >= data.size()) {
if (m_framesAvail[i] && m_framesAvail[i]->capacity >= dataSize) {
// is it smaller than the last found?
if (found < 0 ||
m_framesAvail[i]->capacity < m_framesAvail[found]->capacity) {
@@ -272,7 +333,7 @@ void SourceImpl::PutFrame(VideoMode::PixelFormat pixelFormat,
// if nothing found, allocate a new buffer
if (found < 0)
frameData.reset(new Frame::Data{data.size()});
frameData.reset(new Frame::Data{dataSize});
else
frameData = std::move(m_framesAvail[found]);
}
@@ -280,14 +341,22 @@ void SourceImpl::PutFrame(VideoMode::PixelFormat pixelFormat,
// Initialize frame data
frameData->refcount = 0;
frameData->time = time;
frameData->size = data.size();
frameData->size = dataSize;
frameData->pixelFormat = pixelFormat;
// Copy in image data
DEBUG4("Copying data to " << ((void*)frameData->data) << " from "
<< ((void*)data.data()) << " (" << data.size()
<< " bytes)");
std::memcpy(frameData->data, data.data(), data.size());
<< " bytes)" << (addDHT ? ", adding DHT" : ""));
if (addDHT) {
// Insert DHT data immediately before SOF
std::memcpy(frameData->data, data.data(), locSOF);
std::memcpy(frameData->data + locSOF, dhtData, sizeof(dhtData));
std::memcpy(frameData->data + locSOF + sizeof(dhtData),
data.data() + locSOF, data.size() - locSOF);
} else {
std::memcpy(frameData->data, data.data(), data.size());
}
// Update frame
{