/// <summary>
/// Constructor.
/// </summary>
/// <param name="id"></param>
/// <param name="stream"></param>
/// <param name="start"></param>
/// <param name="end"></param>
/// <param name="queue"></param>
/// <param name="imgFiles"></param>
public ImageFilesThread(int id, BufferedStream stream, long start, long end, BlockingCollection <int> queue, ImageFiles imgFiles)
{
this.id = id;
this.stream = stream;
this.imgFiles = imgFiles;
this.start = start;
this.end = end; // inclusive
this.queue = queue;
}
/// <summary>
/// Begins the process of removing image block from phone's memory by calling several methods of ImageFiles.
/// </summary>
/// <param name="filterResult">The blocks remianing after block hash filtering. It is modified to being free from any image blocks too, by the end of the method.</param>
/// <param name="imageFiles">The image blocks that were previosuly located on the phone's memory.</param>
public static FilterResult FilterOutImages(FilterResult filterResult, ImageFiles imageFiles)
{
List <ImageBlock> reduced = RemoveImages(imageFiles.ImageBlocks, filterResult);
WorkerThread.write("Filtered {0} images", imageFiles.ImageBlocks.Count - reduced.Count);
long oldFilteredCount = filterResult.FilteredBytesCount;
filterResult = FilterImageBlocks(imageFiles, filterResult);
WorkerThread.write("Filtered an additional {0} bytes", filterResult.FilteredBytesCount - oldFilteredCount);
imageFiles.ImageBlocks = reduced;
return(filterResult);
}
/// <summary>
/// Calls methods to begin locating image blocks in the memory file.
/// </summary>
/// <param name="filePath">Path of the phone's memory file.</param>
/// <returns>A list of image blocks present in the phone's memory.</returns>
public static ImageFiles LocateImages(string filePath)
{
ImageFiles imageFiles = null;
try {
imageFiles = new ImageFiles(filePath);
imageFiles.Process();
imageFiles.Close();
} catch (Exception ex) {
WorkerThread.write("Error locating images: " + ex.Message);
} finally {
if (imageFiles != null)
{
imageFiles.Close();
}
else
{
imageFiles = new ImageFiles();
}
}
return(imageFiles);
}
/// <summary>
/// Called after two independant operations have been performed: finding
/// images in the memory, and excluding memory blocks because their hashes
/// were known. Here we further reduce the memory that we'll use for
/// searching for fields by removing memory consumed by images.
/// </summary>
/// <param name="imageFiles">Locations of found memory files.</param>
/// <param name="filterResult">The filtered memory blocks.</param>
/// <returns>An updated filtered memory block object.</returns>
private static FilterResult FilterImageBlocks(ImageFiles imageFiles, FilterResult filterResult)
{
int imgCount = imageFiles.ImageBlocks.Count;
if (imgCount == 0)
{
// No images had been found: nothing to do.
return(filterResult);
}
bool foundOverlap = false;
List <Block> reducedUnfilteredBlocks = new List <Block>();
// For each memory block, update it if it contains all or part of an image.
foreach (Block block in filterResult.UnfilteredBlocks)
{
long blockStart = block.OffsetFile;
long blockEnd = blockStart + block.Length - 1; // inclusive
bool modified = false;
int indx = 0;
// Go through the images and see if one is contained in the
// memory block.
while (!modified && (indx < imgCount))
{
long imgStart = imageFiles.ImageBlocks[indx].Offset;
if (blockEnd < imgStart)
{
// We can assume image locations are ordered, so we can
// stop looking. All subsequent images will start after
// this memory block. Move on to the next block.
break;
}
long imgEnd = imgStart + imageFiles.ImageBlocks[indx].Length - 1; // inclusive
if (blockStart > imgEnd)
{
// The image ends before the block starts.
indx++;
continue;
}
if (((blockStart >= imgStart) && (blockStart <= imgEnd)) ||
((blockEnd >= imgStart) && (blockEnd <= imgEnd)) ||
((imgStart >= blockStart) && (imgStart <= blockEnd)) ||
((imgEnd >= blockStart) && (imgEnd <= blockEnd)))
{
// All or part of the image is within the memory block.
modified = true;
foundOverlap = true;
List <Block> reduced = RemoveImageBlock(block, imageFiles.ImageBlocks[indx]);
if (reduced.Count == 1)
{
reducedUnfilteredBlocks.Add(reduced[0]);
}
else if (reduced.Count > 0)
{
reducedUnfilteredBlocks.AddRange(reduced);
}
// It's possible there are more images that overlap, but
// we'll get them in a recursive call.
break;
}
indx++;
}
if (!modified)
{
reducedUnfilteredBlocks.Add(block);
}
}
// If we didn't find any overlaps, we're done.
if (!foundOverlap)
{
return(filterResult);
}
long unfilteredCount = 0;
foreach (Block block in reducedUnfilteredBlocks)
{
unfilteredCount += block.Length;
}
long filteredCount = filterResult.FilteredBytesCount + (filterResult.UnfilteredBytesCount - unfilteredCount);
// A block can have multiple images within it. We remove one image
// at a time, so we recursively call this function to remove images
// from updated blocks. It may not be the most efficient method,
// but it's a little cleaner.
FilterResult newFilterResult = new FilterResult
{
Duration = filterResult.Duration,
FilteredBytesCount = filteredCount,
UnfilteredBytesCount = unfilteredCount,
UnfilteredBlocks = reducedUnfilteredBlocks
};
return(FilterImageBlocks(imageFiles, newFilterResult));
}
/// <summary>
/// This is where all of the work is done to extract information from
/// the phone's binary file.
/// It calls methods for image block identification, removal, block hash filtering, field and record level Viterbi infrerence, postprocessing of results.
/// </summary>
private void Run()
{
bool success = false;
PostProcessor postProcess = null;
PhoneInfo phoneInfo = null;
try
{
// Use the SHA1 of the binary file to identify it.
_canAbort = true;
StartStep(1);
write("Calculating file SHA1");
fileSha1 = DcUtils.CalculateFileSha1(this.filePath);
if (_cancel)
{
return;
}
NextStep(1);
// We scan the file to locate images. This is done independent
// of block hashes.
write("Extracting graphical images");
#if LOADONLY || SKIPIMAGES
ImageFiles imageFiles = new ImageFiles();
#else
ImageFiles imageFiles = ImageFiles.LocateImages(this.filePath);
if (_cancel)
{
return;
}
_canAbort = false;
write("Extracted {0} graphical images", imageFiles.ImageBlocks.Count);
#endif
NextStep(2);
if (_cancel)
{
return;
}
// Load the block hashes into the DB (if they're not already
// there).
HashLoader.HashLoader hashloader = HashLoader.HashLoader.LoadHashesIntoDB(fileSha1, this.filePath, this.manufacturer,
this.model, this.note, this.doNotStoreHashes);
if (_cancel || (hashloader == null))
{
return;
}
int phoneId = hashloader.PhoneId;
#if LOADONLY
_cancel = true;
return;
#endif
_canAbort = true;
NextStep(3);
if (_cancel)
{
return;
}
// Identify block hashes that are already in the DB, which we
// will then filter out.
FilterResult filterResult = RunBlockHashFilter(fileSha1, phoneId, hashloader.GetAndForgetStoredHashes());
hashloader = null;
NextStep(4);
// Since images were located before block hash filter, forget
// about any image that overlaps a filtered block hash.
write("Filtering image locations");
//filterResult = ImageFiles.FilterOutImages(filterResult, imageFiles);
//Dump_Filtered_Blocks(filterResult, filePath);
NextStep(5);
// Finally, we're ready to use the Viterbi state machine.
// Start by identifying fields.
ViterbiResult viterbiResultFields = RunViterbi(filterResult, fileSha1);
// Allow garbage collection.
filterResult.UnfilteredBlocks.Clear();
NextStep(6);
List <MetaField> addressBookEntries = new List <MetaField>();
List <MetaField> callLogs = new List <MetaField>();
List <MetaField> sms = new List <MetaField>();
// Second run of Viterbi, this time for records.
//ViterbiResult viterbiResultRecord = RunMetaViterbi(viterbiResultFields,addressBookEntries,callLogs,sms);
RunMetaViterbi(viterbiResultFields, addressBookEntries, callLogs, sms);
viterbiResultFields = null;
NextStep(7);
// Perform post processing. This may remove some records.
postProcess = new PostProcessor(callLogs, addressBookEntries, sms, imageFiles.ImageBlocks);
success = PerformPostProcessing(postProcess);
NextStep(8);
GTC_CSV_Writer wr = new GTC_CSV_Writer(this.metaResults, postProcess, filePath);
wr.Write_CSV();
wr.Write_Field_Paths(this.fieldPaths);
// Finished.
phoneInfo = new PhoneInfo(manufacturer, model, note, doNotStoreHashes);
write("Finished work");
FinishedStep(9);
}
finally
{
if (_cancel)
{
MainForm.Program.EndWork(false, null, null, null);
}
else
{
MainForm.Program.EndWork(success, postProcess, this.filePath, phoneInfo);
}
}
}
