protected Mp3XingBlock(byte[] frameBuf, int xix, Mp3Header header, string xingString)
{
this.buf = frameBuf;
this.header = header;
this.xingIx = xix;
this.XingString = xingString;
int ix = xingIx + 8;
if (HasFrameCount)
{
this.FrameCount = ConvertTo.FromBig32ToInt32(frameBuf, ix);
ix += 4;
}
if (HasSize)
{
this.XingSize = ConvertTo.FromBig32ToInt32(frameBuf, ix);
ix += 4;
}
if (HasTableOfContents)
{
this.tocOffset = ix;
ix += 100;
}
if (HasQualityIndicator)
{
this.QualityIndicator = ConvertTo.FromBig32ToInt32(frameBuf, ix);
}
}
public static Mp3XingBlock.Model Create(byte[] buf, Mp3Header header)
{
System.Diagnostics.Debug.Assert(header.IsMpegLayer3);
int xix = header.XingOffset;
string xingString = ConvertTo.FromAsciiToString(buf, xix, 4);
if (xingString == "Info" || xingString == "Xing")
{
string lameString = ConvertTo.FromAsciiToString(buf, xix + 0x78, 9);
if (lameString.StartsWith("LAME"))
{
return(new Mp3LameBlock.Model(buf, xix, header, xingString, lameString));
}
else
{
return(new Mp3XingBlock.Model(buf, xix, header, xingString));
}
}
return(null);
}
private void GetDiagnostics()
{
if (Data.Header.BitRate == null)
{
IssueModel.Add("Invalid bit rate.");
}
if (Data.Header.ChannelMode != Mp3ChannelMode.JointStereo)
{
IssueTags tags = Data.Header.ChannelMode == Mp3ChannelMode.Stereo? IssueTags.Overstandard : IssueTags.Substandard;
IssueModel.Add($"Channel mode is {Data.Header.ChannelMode}.", Severity.Advisory, tags);
}
if (Data.Header.SampleRate < 44100)
{
IssueModel.Add($"Frequency is {Data.Header.SampleRate} Hz (expecting 44100 or better)", Severity.Advisory, IssueTags.Substandard);
}
else if (Data.Header.SampleRate > 44100)
{
IssueModel.Add($"Frequency is {Data.Header.SampleRate}", Severity.Advisory, IssueTags.Overstandard);
}
if (Data.Xing != null)
{
if (Data.Header.CrcProtectedBit == 0)
{
IssueModel.Add("Header not flagged for CRC protection.", Severity.Noise);
}
if (!Data.Xing.HasFrameCount)
{
IssueModel.Add("Missing XING frame count.");
}
if (!Data.Xing.HasSize)
{
IssueModel.Add("Missing XING file size.");
}
if (!Data.Xing.HasTableOfContents)
{
IssueModel.Add("Missing XING table of contents.");
}
else
if (Data.Xing.IsTocCorrupt())
{
IssueModel.Add("XING table of contents is corrupt.");
}
if (Data.Xing.HasQualityIndicator)
{
var qi = Data.Xing.QualityIndicator;
if (qi < 0 || qi > 100)
{
IssueModel.Add($"Quality indicator of {qi} is out of range.");
}
else
if (Data.Lame != null && Data.Lame.IsVbr && qi < 78)
{
IssueModel.Add($"VBR quality of {qi} is substandard.", Severity.Advisory, IssueTags.Substandard);
}
}
}
if (Data.Lame == null)
{
IssueModel.Add("Not a LAME encoding.", Severity.Advisory, IssueTags.Substandard);
}
else
{
var isBlessed = blessedLames.Any(item => item == Data.Lame.LameVersion);
if (!isBlessed)
{
IssueModel.Add("LAME version is not favored.", Severity.Advisory, IssueTags.Substandard);
}
if (Data.Lame.LameSize != Data.MediaCount)
{
IssueModel.Add("Indicated LAME audio size incorrect or unrecognized tag block.", Severity.Warning);
}
if (Data.Lame.TagRevision == 0xF)
{
IssueModel.Add($"Tag revision {Data.Lame.TagRevision} invalid.");
}
if (Data.Lame.BitrateMethod == 0 || Data.Lame.BitrateMethod == 0xF)
{
IssueModel.Add($"Bitrate method {Data.Lame.BitrateMethod} invalid.");
}
if (Data.Lame.IsAbr)
{
IssueModel.Add("ABR encoding method is obsolete.", Severity.Advisory, IssueTags.Substandard);
}
if (Data.Lame.AudiophileReplayGain != 0)
{
IssueModel.Add($"Audiophile ReplayGain ({Data.Lame.AudiophileReplayGain}) usage is obsolete.", Severity.Advisory, IssueTags.Substandard);
}
if (Data.Lame.IsCbr && Mp3Header.IsBadCbr(Data.Header.MpegVersionBits, Data.Lame.MinBitRate))
{
IssueModel.Add($"Minimum bit rate of {Data.Lame.MinBitRate} not valid.", Severity.Advisory, IssueTags.Substandard);
}
}
if (Data.HasId3v1)
{
if (Data.HasId3v1Phantom)
{
IssueModel.Add("Has phantom ID3v1 tag block.",
Severity.Warning, IssueTags.Fussy | IssueTags.HasId3v1,
"Remove phantom ID3v1 tag block", RepairPhantomTag);
}
else
{
var minor = GetMinorOfV1(Data.id3v1Block);
Severity sev = minor == 0? Severity.Warning : Severity.Noise;
IssueModel.Add($"Has ID3v1.{minor} tags.", sev, IssueTags.HasId3v1);
}
}
if (!Data.HasId3v2)
{
IssueModel.Add("Missing ID3v2 tags.", Severity.Trivia, IssueTags.Fussy | IssueTags.Substandard);
}
else
{
switch (Data.Id3v2Major)
{
case 2:
IssueModel.Add("Has obsolete ID3v2.2 tags.", Severity.Warning, IssueTags.Fussy | IssueTags.Substandard);
break;
case 3:
// Hunky dory!
break;
case 4:
IssueModel.Add("Has jumped-the-shark ID3v2.4 tags.", Severity.Trivia);
break;
default:
IssueModel.Add("Has ID3 tags of unknown version 2." + Data.Id3v2Major);
break;
}
if (Data.Id3v2TagRepair != null)
{
IssueModel.Add($"ID3v2 tag size over by 1 (repair with {Data.Id3v2TagRepair}).",
Severity.Warning, IssueTags.Fussy,
"Patch EAC induced ID3v2 tag size error", RepairId3v2OffBy1);
}
}
if (Data.HasApe)
{
IssueModel.Add("Has APE tags.", Severity.Trivia, IssueTags.HasApe);
}
if (Data.HasLyrics3)
{
IssueModel.Add("Has obsolete Lyrics3v2 block.", Severity.Advisory);
}
if (Data.DeadBytes != 0)
{
IssueModel.Add($"Dead space preceeds audio, size={Data.DeadBytes}", Severity.Warning, IssueTags.Substandard);
}
}
public Model(byte[] hdr, int xingIx, Mp3Header header, string xingText) => _data = new Mp3XingBlock(hdr, xingIx, header, xingText);
private Mp3LameBlock(byte[] buf, int xix, Mp3Header header, string xingString, string lameString) : base(buf, xix, header, xingString)
=> LameVersion = lameString;
public Model(byte[] buf, int hix, Mp3Header header, string xingString, string lameString) => base._data = new Mp3LameBlock(buf, hix, header, xingString, lameString);