mpeg decoder: improved file type detection

git-svn-id: http://svn.code.sf.net/p/qmmp-dev/code/trunk/qmmp@6628 90c681e8-e032-0410-971d-27865f9a5e38

2 files changed, 34 insertions, 22 deletions

diff --git a/src/plugins/Input/mad/decodermadfactory.cpp b/src/plugins/Input/mad/decodermadfactory.cpp
index ec64c92ae..c3aebda8a 100644
--- a/src/plugins/Input/mad/decodermadfactory.cpp
+++ b/src/plugins/Input/mad/decodermadfactory.cpp
@@ -60,24 +60,50 @@ DecoderMADFactory::DecoderMADFactory()
 
 bool DecoderMADFactory::canDecode(QIODevice *input) const
 {
-    char buf[16 * 512];
+    char buf[8192];
+    qint64 buf_at = sizeof(buf);
 
-    if (input->peek(buf,sizeof(buf)) == sizeof(buf))
+    if(input->peek(buf, sizeof(buf)) != sizeof(buf))
+        return false;
+
+    if (!memcmp(buf + 8, "WAVE", 4) && !memcmp(buf + 20, "U" ,1))
+        return true;
+
+    if(!memcmp(buf, "ID3", 3))
     {
-        if (!memcmp(buf + 8, "WAVE", 4) && !memcmp(buf + 20, "U" ,1))
-            return true;
+        TagLib::ByteVector byteVector(buf, sizeof(buf));
+        TagLib::ID3v2::Header header(byteVector);
+
+        //skip id3v2tag if possible
+        if(input->isSequential())
+        {
+            if(header.tagSize() >= sizeof(buf))
+                return false;
+
+            buf_at = sizeof(buf) - header.tagSize();
+            memmove(buf, buf + header.tagSize() + header.tagSize(), sizeof(buf) - header.tagSize());
+        }
+        else
+        {
+            input->seek(header.tagSize());
+            buf_at = input->read(buf, sizeof(buf));
+            input->seek(0);
+        }
+    }
 
+    if(buf_at > 0)
+    {
         struct mad_stream stream;
         struct mad_header header;
         int dec_res;
 
         mad_stream_init (&stream);
         mad_header_init (&header);
-        mad_stream_buffer (&stream, (unsigned char *) buf, sizeof(buf));
+        mad_stream_buffer (&stream, (unsigned char *) buf, buf_at);
         stream.error = MAD_ERROR_NONE;
 
         while ((dec_res = mad_header_decode(&header, &stream)) == -1
-                && MAD_RECOVERABLE(stream.error))
+               && MAD_RECOVERABLE(stream.error))
             ;
         return dec_res != -1 ? true: false;
     }
diff --git a/src/qmmp/decoder.cpp b/src/qmmp/decoder.cpp
index d2b84c1bd..1170b0afe 100644
--- a/src/qmmp/decoder.cpp
+++ b/src/qmmp/decoder.cpp
@@ -157,17 +157,6 @@ DecoderFactory *Decoder::findByFilePath(const QString &path, bool useContent)
             qWarning("Decoder: file open error: %s", qPrintable(file.errorString()));
             return 0;
         }
-        QByteArray array = file.read(8192);
-        QBuffer buffer(&array);
-        buffer.open(QIODevice::ReadOnly);
-
-        //try last factory with stream based input or local files support
-        if (fact && isEnabled(fact) && (!fact->properties().noInput ||
-                                        fact->properties().protocols.contains("file")))
-        {
-            if(fact->canDecode(&buffer))
-                return fact;
-        }
 
         foreach(QmmpPluginCache *item, *m_cache)
         {
@@ -179,7 +168,7 @@ DecoderFactory *Decoder::findByFilePath(const QString &path, bool useContent)
             if(fact && fact->properties().noInput && !fact->properties().protocols.contains("file"))
                 continue;
 
-            if (fact->canDecode(&buffer))
+            if (fact->canDecode(&file))
                 return fact;
         }
         return 0;
@@ -219,13 +208,10 @@ DecoderFactory *Decoder::findByFilePath(const QString &path, bool useContent)
             qWarning("Decoder: file open error: %s", qPrintable(file.errorString()));
             return 0;
         }
-        QByteArray array = file.read(8192);
-        QBuffer buffer(&array);
-        buffer.open(QIODevice::ReadOnly);
 
         foreach (fact, filered)
         {
-            if(fact->canDecode(&buffer))
+            if(fact->canDecode(&file))
                 return fact;
         }
         return 0;