1 files changed, 119 insertions, 0 deletions
diff --git a/kopete/protocols/msn/webcam/libmimic/vlc_decode.c b/kopete/protocols/msn/webcam/libmimic/vlc_decode.c
new file mode 100644
index 00000000..5675342d
--- /dev/null
+++ b/kopete/protocols/msn/webcam/libmimic/vlc_decode.c
@@ -0,0 +1,119 @@
+/* Copyright (C) 2005  Ole André Vadla Ravnås <oleavr@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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
+ */
+
+#include <string.h>
+#include "mimic-private.h"
+
+extern guchar _col_zag[64];
+
+/*
+ * _vlc_decode_block
+ *
+ * De-serialize (reconstruct) a variable length coded 8x8 block.
+ */
+gboolean _vlc_decode_block(MimCtx *ctx, gint *block, gint num_coeffs)
+{
+    guint pos;
+
+    memset(block, 0, 64 * sizeof(gint));
+
+    /* The DC-value is read in as is. */
+    block[0] = _read_bits(ctx, 8);
+
+    for (pos = 1; pos < num_coeffs; pos++) {
+        
+        guint prev_data_index, prev_cur_chunk_len, prev_chunk;
+        guint value, num_bits;
+        gboolean prev_read_odd, found_magic;
+        
+        /* Save context. */
+        prev_data_index = ctx->data_index;
+        prev_cur_chunk_len = ctx->cur_chunk_len;
+        prev_chunk = ctx->cur_chunk;
+        prev_read_odd = ctx->read_odd;
+
+        /* Grab 16 bits. */
+        value = _read_bits(ctx, 16) << 16;
+
+        /* Restore context. */
+        ctx->data_index = prev_data_index;
+        ctx->cur_chunk_len = prev_cur_chunk_len;
+        ctx->cur_chunk = prev_chunk;
+        ctx->read_odd = prev_read_odd;
+
+        /* Analyze and determine number of bits to read initially. */
+        num_bits = 3;
+        if ((value >> 30) == 0 || (value >> 30) == 1) {
+            num_bits = 2;
+        } else if ((value & 0xE0000000) != 0x80000000) {
+            guint nibble = value >> 28;
+
+            if (nibble == 11 || nibble == 12) {
+                num_bits = 4;
+            } else if (nibble == 10) {
+                _read_bits(ctx, 4);
+
+                return TRUE;
+            } else {
+                if (((value << 2) & 0x8000000) == 0)
+                    num_bits = 2;
+
+                num_bits += 2;
+            }
+        }
+
+        /* Read that number of bits. */
+        value = _read_bits(ctx, num_bits);
+
+        /*
+         * Look up the current value against the magic ones,
+         * and continue extending it bit by bit from the input
+         * stream until the magic value is found or we have
+         * read 32 bits (in which case we give up).
+         */
+        found_magic = FALSE;
+        while (!found_magic) {
+            VlcMagic *magic;
+
+            if (num_bits > 32)
+                return FALSE;
+
+            magic = _find_magic(value);
+
+            if (magic != NULL) {
+                pos += magic->pos_add;
+                num_bits = magic->num_bits;
+
+                found_magic = TRUE;
+            } else {
+                value <<= 1;
+                value |= _read_bits(ctx, 1);
+
+                num_bits++;
+            }
+        }
+
+        /* Read the number of bits given by magic value entry. */
+        value = _read_bits(ctx, num_bits);
+        
+        /* Gotcha! :-) */
+        block[_col_zag[pos]] = ctx->vlcdec_lookup[(num_bits * 255) + value];
+    }
+
+    return TRUE;
+}
+