int RemoteCameraHttp::Capture( Image &image )
{
int content_length = GetResponse();
if ( content_length == 0 )
{
Warning( "Unable to capture image, retrying" );
return( 1 );
}
if ( content_length < 0 )
{
Error( "Unable to get response" );
Disconnect();
return( -1 );
}
switch( format )
{
case JPEG :
{
if ( !image.DecodeJpeg( buffer.extract( content_length ), content_length, colours, subpixelorder ) )
{
Error( "Unable to decode jpeg" );
Disconnect();
return( -1 );
}
break;
}
case X_RGB :
{
if ( content_length != image.Size() )
{
Error( "Image length mismatch, expected %d bytes, content length was %d", image.Size(), content_length );
Disconnect();
return( -1 );
}
image.Assign( width, height, colours, subpixelorder, buffer, imagesize );
break;
}
case X_RGBZ :
{
if ( !image.Unzip( buffer.extract( content_length ), content_length ) )
{
Error( "Unable to unzip RGB image" );
Disconnect();
return( -1 );
}
image.Assign( width, height, colours, subpixelorder, buffer, imagesize );
break;
}
default :
{
Error( "Unexpected image format encountered" );
Disconnect();
return( -1 );
}
}
return( 0 );
}
int cURLCamera::Capture( Image &image ) {
bool frameComplete = false;
/* MODE_STREAM specific variables */
bool SubHeadersParsingComplete = false;
unsigned int frame_content_length = 0;
std::string frame_content_type;
bool need_more_data = false;
int nRet;
/* Grab the mutex to ensure exclusive access to the shared data */
lock();
while ( !frameComplete ) {
/* If the work thread did a reset, reset our local variables */
if ( bReset ) {
SubHeadersParsingComplete = false;
frame_content_length = 0;
frame_content_type.clear();
need_more_data = false;
bReset = false;
}
if ( mode == MODE_UNSET ) {
/* Don't have a mode yet. Sleep while waiting for data */
nRet = pthread_cond_wait(&data_available_cond,&shareddata_mutex);
if ( nRet != 0 ) {
Error("Failed waiting for available data condition variable: %s",strerror(nRet));
return -20;
}
}
if ( mode == MODE_STREAM ) {
/* Subheader parsing */
while( !SubHeadersParsingComplete && !need_more_data ) {
size_t crlf_start, crlf_end, crlf_size;
std::string subheader;
/* Check if the buffer contains something */
if ( databuffer.empty() ) {
/* Empty buffer, wait for data */
need_more_data = true;
break;
}
/* Find crlf start */
crlf_start = memcspn(databuffer,"\r\n",databuffer.size());
if ( crlf_start == databuffer.size() ) {
/* Not found, wait for more data */
need_more_data = true;
break;
}
/* See if we have enough data for determining crlf length */
if ( databuffer.size() < crlf_start+5 ) {
/* Need more data */
need_more_data = true;
break;
}
/* Find crlf end and calculate crlf size */
crlf_end = memspn(((const char*)databuffer.head())+crlf_start,"\r\n",5);
crlf_size = (crlf_start + crlf_end) - crlf_start;
/* Is this the end of a previous stream? (This is just before the boundary) */
if ( crlf_start == 0 ) {
databuffer.consume(crlf_size);
continue;
}
/* Check for invalid CRLF size */
if ( crlf_size > 4 ) {
Error("Invalid CRLF length");
}
/* Check if the crlf is \n\n or \r\n\r\n (marks end of headers, this is the last header) */
if( (crlf_size == 2 && memcmp(((const char*)databuffer.head())+crlf_start,"\n\n",2) == 0) || (crlf_size == 4 && memcmp(((const char*)databuffer.head())+crlf_start,"\r\n\r\n",4) == 0) ) {
/* This is the last header */
SubHeadersParsingComplete = true;
}
/* Copy the subheader, excluding the crlf */
subheader.assign(databuffer, crlf_start);
/* Advance the buffer past this one */
databuffer.consume(crlf_start+crlf_size);
Debug(7,"Got subheader: %s",subheader.c_str());
/* Find where the data in this header starts */
size_t subheader_data_start = subheader.rfind(' ');
if ( subheader_data_start == std::string::npos ) {
subheader_data_start = subheader.find(':');
}
/* Extract the data into a string */
std::string subheader_data = subheader.substr(subheader_data_start+1, std::string::npos);
Debug(8,"Got subheader data: %s",subheader_data.c_str());
/* Check the header */
if(strncasecmp(subheader.c_str(),content_length_match,content_length_match_len) == 0) {
/* Found the content-length header */
frame_content_length = atoi(subheader_data.c_str());
Debug(6,"Got content-length subheader: %d",frame_content_length);
} else if(strncasecmp(subheader.c_str(),content_type_match,content_type_match_len) == 0) {
/* Found the content-type header */
frame_content_type = subheader_data;
Debug(6,"Got content-type subheader: %s",frame_content_type.c_str());
}
}
/* Attempt to extract the frame */
if(!need_more_data) {
if(!SubHeadersParsingComplete) {
/* We haven't parsed all headers yet */
need_more_data = true;
} else if ( ! frame_content_length ) {
/* Invalid frame */
Error("Invalid frame: invalid content length");
} else if ( frame_content_type != "image/jpeg" ) {
/* Unsupported frame type */
Error("Unsupported frame: %s",frame_content_type.c_str());
} else if(frame_content_length > databuffer.size()) {
/* Incomplete frame, wait for more data */
need_more_data = true;
} else {
/* All good. decode the image */
image.DecodeJpeg(databuffer.extract(frame_content_length), frame_content_length, colours, subpixelorder);
frameComplete = true;
}
}
/* Attempt to get more data */
if(need_more_data) {
nRet = pthread_cond_wait(&data_available_cond,&shareddata_mutex);
if(nRet != 0) {
Error("Failed waiting for available data condition variable: %s",strerror(nRet));
return -18;
}
need_more_data = false;
}
} else if(mode == MODE_SINGLE) {
/* Check if we have anything */
if (!single_offsets.empty()) {
if( (single_offsets.front() > 0) && (databuffer.size() >= single_offsets.front()) ) {
/* Extract frame */
image.DecodeJpeg(databuffer.extract(single_offsets.front()), single_offsets.front(), colours, subpixelorder);
single_offsets.pop_front();
frameComplete = true;
} else {
/* This shouldn't happen */
Error("Internal error. Attempting recovery");
databuffer.consume(single_offsets.front());
single_offsets.pop_front();
}
} else {
/* Don't have a frame yet, wait for the request complete condition variable */
nRet = pthread_cond_wait(&request_complete_cond,&shareddata_mutex);
if(nRet != 0) {
Error("Failed waiting for request complete condition variable: %s",strerror(nRet));
return -19;
}
}
} else {
/* Failed to match content-type */
Fatal("Unable to match Content-Type. Check URL, username and password");
} /* mode */
} /* frameComplete loop */
/* Release the mutex */
unlock();
if(!frameComplete)
return -1;
return 1;
}
