gst/rtp/Makefile.am: gst/rtp/fnv1hash.c (MASK_24, FNV1_HASH_32_INIT, FNV1_HASH_32_PRIME, fnv1_hash_32_new, fnv1_hash_...

Original commit message from CVS:
* gst/rtp/Makefile.am:
* gst/rtp/fnv1hash.c (MASK_24, FNV1_HASH_32_INIT, FNV1_HASH_32_PRIME,
fnv1_hash_32_new, fnv1_hash_32_update, fnv1_hash_32_to_24):
* gst/rtp/fnv1hash.h (__GST_FNV1_HASH_H__):
Add a simple hashing implementation that we can use to generate
a 24-bit ident value based on the codebooks for vorbis and theora.
* gst/rtp/gstrtptheorapay.c (gst_rtp_theora_pay_finish_headers,
gst_rtp_theora_pay_handle_buffer):
* gst/rtp/gstrtpvorbisdepay.c
(gst_rtp_vorbis_depay_parse_configuration,
gst_rtp_vorbis_depay_switch_codebook, gst_rtp_vorbis_depay_process):
* gst/rtp/gstrtpvorbispay.c (gst_rtp_vorbis_pay_reset_packet,
gst_rtp_vorbis_pay_init_packet, gst_rtp_vorbis_pay_flush_packet,
gst_rtp_vorbis_pay_finish_headers, gst_rtp_vorbis_pay_handle_buffer):
Use the hashing function, ensuring that the same codebooks result
in the same ident and thus the same SDP description.
Various log fixes/changes.

1 files changed, 61 insertions, 0 deletions

diff --git a/gst/rtp/fnv1hash.c b/gst/rtp/fnv1hash.c
new file mode 100644
index 00000000..84fac9ad
--- /dev/null
+++ b/gst/rtp/fnv1hash.c
@@ -0,0 +1,61 @@
+/* GStreamer
+ * Copyright (C) 2007 Thomas Vander Stichele <thomas at apestaart dot org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <glib.h>
+
+/* This file implements FNV-1 hashing used in the Ogg payload encoders
+ * to generate the 24-bit ident value based on the header pages.
+ * See http://isthe.com/chongo/tech/comp/fnv/
+ */
+
+#define MASK_24 (((guint32) 1 << 24) -1)
+
+#define FNV1_HASH_32_INIT ((guint32) 0x811C9DC5L)
+//2166136261L)
+#define FNV1_HASH_32_PRIME 16777619
+
+guint32
+fnv1_hash_32_new (void)
+{
+  return FNV1_HASH_32_INIT;
+}
+
+guint32
+fnv1_hash_32_update (guint32 hash, const guchar * data, guint length)
+{
+  guint i;
+  const guchar *p = data;
+
+  for (i = 0; i < length; ++i, ++p) {
+    hash *= FNV1_HASH_32_PRIME;
+    hash ^= *p;
+  }
+
+  return hash;
+}
+
+guint32
+fnv1_hash_32_to_24 (guint32 hash)
+{
+  return (hash >> 24) ^ (hash & MASK_24);
+}