Changeset a9bc769eafbfe07e8782859c69e325e5c7859585

Timestamp:

22/11/02 00:06:08 (6 years ago)

Author:

Christophe Massiot <massiot@videolan.org>

git-committer:

Christophe Massiot <massiot@videolan.org> 1037919968 +0000

git-parent:

[e9e8b069d0538fd3551bae5f0c30fb7457939a7e]

git-author:

Christophe Massiot <massiot@videolan.org> 1037919968 +0000

Message:

Channel reordering according to the WG-4 specification, courtesy of
Heiko Panther.

Files:

• modules/audio_filter/converter/a52tofloat32.c (modified) (2 diffs)

modules/audio_filter/converter/a52tofloat32.c

@@ -5 +5 @@
- *****************************************************************************
- * Copyright (C) 2001, 2002 VideoLAN
-7 2002/11/18 23:00:41
+8 2002/11/21 23:06:08
- *
- * Authors: Gildas Bazin <gbazin@netcourrier.com>
@@ -216 +216 @@
-static void Interleave( float * p_out, const float * p_in, int i_nb_channels )
-{
+    /* We do not only have to interleave, but also reorder the channels
+     * Channel reordering according to number of output channels of libA52
+     * The reordering needs to be different for different channel configurations
+     * (3F2R, 1F2R etc), so this is only temporary.
+     * The WG-4 order is appropriate for stereo, quadrophonia, and 5.1 surround.
+     *
+     * 6 channel mode
+     * channel  liba52 order    WG-4 order
+     * 0    LFE     // L
+     * 1    L       // R
+     * 2    C       // LS
+     * 3    R       // RS
+     * 4    LS      // C
+     * 5    RS      // LFE
+     *
+     * The liba52 moves channels to the front if there are unused spaces, so
+     * there is no gap between channels. The translation table says which
+     * channel of the new stream [use the new channel # as index] is taken
+     * from which original channel [use the number from the array to address
+     * the original channel].
+     */
+    
+    static const int translation[7][6] =
+    {{ 0, 0, 0, 0, 0, 0 },  /* 0 channels (rarely used) */
+    { 0, 0, 0, 0, 0, 0 },   /* 1 ch */
+    { 0, 1, 0, 0, 0, 0 },   /* 2 */
+    { 1, 2, 0, 0, 0, 0 },   /* 3 */
+    { 1, 3, 2, 0, 0, 0 },   /* 4 */
+    { 1, 3, 4, 2, 0, 0 },   /* 5 */
+    { 1, 3, 4, 5, 2, 0 }};  /* 6 */
+    
-    int i, j;
-
-    for ( j = 0; j < i_nb_channels; j++ )
-    {
-        for ( i = 0; i < 256; i++ )
-        {
-
+
+
-        }
-    }