/// <summary>
/// This method takes the left channel and right channel wave raw data and analyses it to get
/// the maximum and minimum values in the float structure. It returns a data structure named
/// WaveDataMinMax (see class description for more information). Negative values can be converted to
/// positive values before min and max comparaison. Set this parameter to true for output meters and
/// false for wave form display controls.
/// </summary>
/// <param name="waveDataLeft">Raw wave data (left channel)</param>
/// <param name="waveDataRight">Raw wave data (right channel)</param>
/// <param name="convertNegativeToPositive">Convert negative values to positive values (ex: true when used for output meters,
/// false when used with wave form display controls (since the negative value is used to draw the bottom end of the waveform).</param>
/// <returns>WaveDataMinMax data structure</returns>
public static WaveDataMinMax GetMinMaxFromWaveData(float[] waveDataLeft, float[] waveDataRight, bool convertNegativeToPositive)
{
// Create default data
WaveDataMinMax data = new WaveDataMinMax();
// Loop through values to get min/max
for (int i = 0; i < waveDataLeft.Length; i++)
{
// Set values to compare
float left = waveDataLeft[i];
float right = waveDataRight[i];
// Do we have to convert values before comparaison?
if (convertNegativeToPositive)
{
// Compare values, if negative then remove negative sign
if (left < 0)
{
left = -left;
}
if (right < 0)
{
right = -right;
}
}
// Calculate min/max for left channel
if (left < data.leftMin)
{
data.leftMin = left;
}
if (left > data.leftMax)
{
data.leftMax = left;
}
// Calculate min/max for right channel
if (right < data.rightMin)
{
data.rightMin = right;
}
if (right > data.rightMax)
{
data.rightMax = right;
}
// Calculate min/max mixing both channels
if (left < data.mixMin)
{
data.mixMin = left;
}
if (right < data.mixMin)
{
data.mixMin = right;
}
if (left > data.mixMax)
{
data.mixMax = left;
}
if (right > data.mixMax)
{
data.mixMax = right;
}
}
return data;
}
/// <summary>
/// Reads a peak file and returns a min/max peak list.
/// </summary>
/// <param name="peakFilePath">Peak file path</param>
/// <returns>List of min/max peaks</returns>
public List<WaveDataMinMax> ReadPeakFile(string peakFilePath)
{
// Declare variables
FileStream fileStream = null;
GZipStream gzipStream = null;
BinaryReader binaryReader = null;
List<WaveDataMinMax> listMinMax = new List<WaveDataMinMax>();
string fileHeader = null;
long audioFileLength = 0;
int chunkSize = 0;
int numberOfBlocks = 0;
int currentBlock = 0;
try
{
// Create file stream
fileStream = new FileStream(peakFilePath, FileMode.Open, FileAccess.Read);
binaryReader = new BinaryReader(fileStream);
gzipStream = new GZipStream(fileStream, CompressionMode.Decompress);
// Read file header (34 characters)
// Ex: Sessions Peak File (version# 1.00)
fileHeader = new string(binaryReader.ReadChars(35));
// Extract version and validate
string version = fileHeader.Substring(fileHeader.Length - 5, 4);
if (version != _version)
throw new PeakFileFormatIncompatibleException("Error: The peak file format is not compatible. Expecting version " + _version + " instead of version " + version + ".", null);
// Read audio file length
audioFileLength = binaryReader.ReadInt64();
chunkSize = binaryReader.ReadInt32();
numberOfBlocks = binaryReader.ReadInt32();
// Loop through data
while (binaryReader.PeekChar() != -1)
{
currentBlock++;
// Read peak information and add to list
WaveDataMinMax peak = new WaveDataMinMax();
peak.leftMin = (float)binaryReader.ReadDouble();
peak.leftMax = (float)binaryReader.ReadDouble();
peak.rightMin = (float)binaryReader.ReadDouble();
peak.rightMax = (float)binaryReader.ReadDouble();
peak.mixMin = (float)binaryReader.ReadDouble();
peak.mixMax = (float)binaryReader.ReadDouble();
listMinMax.Add(peak);
}
// Validate number of blocks read
if (currentBlock < numberOfBlocks - 1)
throw new PeakFileCorruptedException("Error: The peak file is corrupted (the number of blocks didn't match)!", null);
}
catch (Exception ex)
{
throw new PeakFileCorruptedException("Error: The peak file is corrupted!", ex);
}
finally
{
gzipStream.Close();
binaryReader.Close();
fileStream.Close();
}
return listMinMax;
}
private void RequestBitmapInternal(Object stateInfo)
{
// Use this instead of a task, this guarantees to execute in another thread
//Console.WriteLine("WaveFormRenderingService - RequestBitmap - boundsBitmap: {0} boundsWaveForm: {1} zoom: {2}", boundsBitmap, boundsWaveForm, zoom);
var request = stateInfo as WaveFormBitmapRequest;
IMemoryGraphicsContext context;
try
{
//Console.WriteLine("WaveFormRenderingService - Creating image cache...");
context = _memoryGraphicsContextFactory.CreateMemoryGraphicsContext(request.BoundsBitmap.Width, request.BoundsBitmap.Height);
if (context == null)
{
Console.WriteLine("Error initializing image cache context!");
return;
}
}
catch (Exception ex)
{
Console.WriteLine("Error while creating image cache context: " + ex.Message);
return;
}
IBasicImage imageCache;
try
{
float x1 = 0;
float x2 = 0;
float leftMin = 0;
float leftMax = 0;
float rightMin = 0;
float rightMax = 0;
float mixMin = 0;
float mixMax = 0;
int historyIndex = 0;
int historyCount = _waveDataCache.Count;
float lineWidth = 0;
int nHistoryItemsPerLine = 0;
const float desiredLineWidth = 0.5f;
WaveDataMinMax[] subset = null;
// Find out how many samples are represented by each line of the wave form, depending on its width.
// For example, if the history has 45000 items, and the control has a width of 1000px, 45 items will need to be averaged by line.
float lineWidthPerHistoryItem = request.BoundsWaveForm.Width / (float)historyCount;
// Check if the line width is below the desired line width
if (lineWidthPerHistoryItem < desiredLineWidth)
{
// Try to get a line width around 0.5f so the precision is good enough and no artifacts will be shown.
while (lineWidth < desiredLineWidth)
{
// Increment the number of history items per line
//Console.WriteLine("Determining line width (lineWidth: " + lineWidth.ToString() + " desiredLineWidth: " + desiredLineWidth.ToString() + " nHistoryItemsPerLine: " + nHistoryItemsPerLine.ToString() + " lineWidthPerHistoryItem: " + lineWidthPerHistoryItem.ToString());
nHistoryItemsPerLine++;
lineWidth += lineWidthPerHistoryItem;
}
nHistoryItemsPerLine--;
lineWidth -= lineWidthPerHistoryItem;
}
else
{
// The lines are larger than 0.5 pixels.
lineWidth = lineWidthPerHistoryItem;
nHistoryItemsPerLine = 1;
}
float heightToRenderLine = 0;
if (request.DisplayType == WaveFormDisplayType.Stereo)
heightToRenderLine = (request.BoundsWaveForm.Height / 4);
else
heightToRenderLine = (request.BoundsWaveForm.Height / 2);
context.DrawRectangle(new BasicRectangle(0, 0, request.BoundsBitmap.Width + 2, request.BoundsBitmap.Height), _brushBackground, _penTransparent);
// The pen cannot be cached between refreshes because the line width changes every time the width changes
//context.SetLineWidth(0.2f);
var penWaveForm = new BasicPen(new BasicBrush(_colorWaveForm), lineWidth);
context.SetPen(penWaveForm);
float startLine = ((int)Math.Floor(request.BoundsBitmap.X / lineWidth)) * lineWidth;
historyIndex = (int) ((startLine / lineWidth) * nHistoryItemsPerLine);
//Console.WriteLine("WaveFormRenderingService - startLine: {0} boundsWaveForm.Width: {1} nHistoryItemsPerLine: {2} historyIndex: {3}", startLine, boundsWaveForm.Width, nHistoryItemsPerLine, historyIndex);
//List<float> roundValues = new List<float>();
float lastLine = startLine + request.BoundsBitmap.Width;
if (request.BoundsWaveForm.Width - request.BoundsBitmap.X < request.BoundsBitmap.Width)
lastLine = request.BoundsWaveForm.Width;
//context.DrawText(string.Format("{0:0.0}", startLine), new BasicPoint(1, request.BoundsBitmap.Height - 10), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
//context.DrawText(string.Format("{0:0.0}", lastLine), new BasicPoint(1, request.BoundsBitmap.Height - 22), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
//context.DrawText(string.Format("{0:0.0}", request.BoundsBitmap.X), new BasicPoint(1, request.BoundsBitmap.Height - 34), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
//context.DrawText(string.Format("{0:0.0}", request.BoundsWaveForm.Width), new BasicPoint(1, request.BoundsBitmap.Height - 46), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
//context.DrawText(string.Format("{0}", request.BoundsBitmap.X), new BasicPoint(1, request.BoundsBitmap.Height - 20), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
//context.DrawText(string.Format("{0:0.0}", request.Zoom), new BasicPoint(1, request.BoundsBitmap.Height - 10), new BasicColor(255, 255, 255), "Roboto Bold", 10 * context.Density);
for (float i = startLine; i < lastLine; i += lineWidth)
{
#if MACOSX
// On Mac, the pen needs to be set every time we draw or the color might change to black randomly (weird?)
context.SetPen(penWaveForm);
#endif
// COMMENTED possible solution for varying line widths rendering problem
// Round to 0.5
//i = (float)Math.Round(i * 2) / 2;
//float iRound = (float)Math.Round(i);
//float iRound = (float)Math.Round(i * 2) / 2;
//float iRound = (float)Math.Round(i * 4) / 4;
// // If this value has already been drawn, skip it (this happens because of the rounding, and this fixes a visual bug)
// if(roundValues.Contains(iRound))
// {
// // Increment the history index; pad the last values if the count is about to exceed
// if (historyIndex < historyCount - 1)
// historyIndex += nHistoryItemsPerLine;
// continue;
// }
// else
// {
// roundValues.Add(iRound);
// }
// Determine the maximum height of a line (+/-)
//Console.WriteLine("WaveForm - Rendering " + i.ToString() + " (rnd=" + iRound.ToString() + ") on " + widthAvailable.ToString());
// Determine x position
// x1 = iRound; //i;
// x2 = iRound; //i;
x1 = i - startLine;
x2 = i - startLine;
if (nHistoryItemsPerLine > 1)
{
if (historyIndex + nHistoryItemsPerLine > historyCount)
{
// Create subset with remaining data
subset = new WaveDataMinMax[historyCount - historyIndex];
_waveDataCache.CopyTo(historyIndex, subset, 0, historyCount - historyIndex);
}
else
{
subset = new WaveDataMinMax[nHistoryItemsPerLine];
_waveDataCache.CopyTo(historyIndex, subset, 0, nHistoryItemsPerLine);
}
leftMin = AudioTools.GetMinPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Left);
leftMax = AudioTools.GetMaxPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Left);
rightMin = AudioTools.GetMinPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Right);
rightMax = AudioTools.GetMaxPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Right);
mixMin = AudioTools.GetMinPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Mix);
mixMax = AudioTools.GetMaxPeakFromWaveDataMaxHistory(subset.ToList(), nHistoryItemsPerLine, ChannelType.Mix);
}
else
{
leftMin = _waveDataCache[historyIndex].leftMin;
leftMax = _waveDataCache[historyIndex].leftMax;
rightMin = _waveDataCache[historyIndex].rightMin;
rightMax = _waveDataCache[historyIndex].rightMax;
mixMin = _waveDataCache[historyIndex].mixMin;
mixMax = _waveDataCache[historyIndex].mixMax;
}
float leftMaxHeight = leftMax * heightToRenderLine;
float leftMinHeight = leftMin * heightToRenderLine;
float rightMaxHeight = rightMax * heightToRenderLine;
float rightMinHeight = rightMin * heightToRenderLine;
float mixMaxHeight = mixMax * heightToRenderLine;
float mixMinHeight = mixMin * heightToRenderLine;
//Console.WriteLine("WaveFormRenderingService - line: {0} x1: {1} x2: {2} historyIndex: {3} historyCount: {4} width: {5}", i, x1, x2, historyIndex, historyCount, boundsWaveForm.Width);
if (request.DisplayType == WaveFormDisplayType.LeftChannel ||
request.DisplayType == WaveFormDisplayType.RightChannel ||
request.DisplayType == WaveFormDisplayType.Mix)
{
// Calculate min/max line height
float minLineHeight = 0;
float maxLineHeight = 0;
// Set mib/max
if (request.DisplayType == WaveFormDisplayType.LeftChannel)
{
minLineHeight = leftMinHeight;
maxLineHeight = leftMaxHeight;
}
else if (request.DisplayType == WaveFormDisplayType.RightChannel)
{
minLineHeight = rightMinHeight;
maxLineHeight = rightMaxHeight;
}
else if (request.DisplayType == WaveFormDisplayType.Mix)
{
minLineHeight = mixMinHeight;
maxLineHeight = mixMaxHeight;
}
// Positive Max Value - Draw positive value (y: middle to top)
context.StrokeLine(new BasicPoint(x1, heightToRenderLine), new BasicPoint(x2, heightToRenderLine - maxLineHeight));
// Negative Max Value - Draw negative value (y: middle to height)
context.StrokeLine(new BasicPoint(x1, heightToRenderLine), new BasicPoint(x2, heightToRenderLine + (-minLineHeight)));
}
else if (request.DisplayType == WaveFormDisplayType.Stereo)
{
// LEFT Channel - Positive Max Value - Draw positive value (y: middle to top)
context.StrokeLine(new BasicPoint(x1, heightToRenderLine), new BasicPoint(x2, heightToRenderLine - leftMaxHeight));
// LEFT Channel - Negative Max Value - Draw negative value (y: middle to height)
context.StrokeLine(new BasicPoint(x1, heightToRenderLine), new BasicPoint(x2, heightToRenderLine + (-leftMinHeight)));
// RIGHT Channel - Positive Max Value (Multiply by 3 to get the new center line for right channel) - Draw positive value (y: middle to top)
context.StrokeLine(new BasicPoint(x1, (heightToRenderLine * 3)), new BasicPoint(x2, (heightToRenderLine * 3) - rightMaxHeight));
// RIGHT Channel - Negative Max Value - Draw negative value (y: middle to height)
context.StrokeLine(new BasicPoint(x1, (heightToRenderLine * 3)), new BasicPoint(x2, (heightToRenderLine * 3) + (-rightMinHeight)));
}
// Increment the history index; pad the last values if the count is about to exceed
if (historyIndex < historyCount - 1)
historyIndex += nHistoryItemsPerLine;
}
}
catch (Exception ex)
{
Console.WriteLine("Error while creating image cache: " + ex.Message);
}
finally
{
// Get image from context (at this point, we are sure the image context has been initialized properly)
//Console.WriteLine("WaveFormRenderingService - Rendering image to memory...");
context.Close();
imageCache = context.RenderToImageInMemory();
}
//Console.WriteLine("WaveFormRenderingService - Created image successfully.");
//stopwatch.Stop();
//Console.WriteLine("WaveFormRenderingService - Created image successfully in {0} ms.", stopwatch.ElapsedMilliseconds);
OnGenerateWaveFormBitmapEnded(new GenerateWaveFormEventArgs()
{
//AudioFilePath = audioFile.FilePath,
OffsetX = request.BoundsBitmap.X,
Zoom = request.Zoom,
Width = context.BoundsWidth,
DisplayType = request.DisplayType,
Image = imageCache
});
}
