ref: 7a7429ef0648823e41180f290a9bcc8513dca15b
parent: 1d4f474b68c0aefba56df59da735658b69da0807
author: cbagwell <cbagwell>
date: Sun Jan 9 11:34:25 EST 2011
Change 24-bit WAV files to use standard channel mappings instead of leaving unassigned to work better for WavPack, Foobar2000, and other apps that expect a mapping to be defined. Patch by David Bryant.
--- a/ChangeLog
+++ b/ChangeLog
@@ -18,6 +18,10 @@
file. Fixed libsox memory leak when closing WavPack files.
(David Bryant)
o Fix RIFF chunk length error when writing 24-bit files. (David Bryant)
+ o 24-bit WAV files were leaving channel maps unassigned. Change to use
+ common channel mappings based on channel count. This allows to
+ work more seemlessly with other apps such as WavPack and Foobar2000.
+ (David Bryant)
Audio device drivers:
--- a/src/wav.c
+++ b/src/wav.c
@@ -1393,12 +1393,25 @@
lsx_writew(ft, wBitsPerSample); /* end info common to all fmts */
if (isExtensible) {+ uint32_t dwChannelMask=0; /* unassigned speaker mapping by default */
static unsigned char const guids[][14] = {"\x00\x00\x00\x00\x10\x00\x80\x00\x00\xAA\x00\x38\x9B\x71", /* wav */
"\x00\x00\x21\x07\xd3\x11\x86\x44\xc8\xc1\xca\x00\x00\x00"}; /* amb */
+
+ /* if not amb, assume most likely channel masks from number of channels; not
+ * ideal solution, but will make files playable in many/most situations
+ */
+ if (strcmp(ft->filetype, "amb")) {+ if (wChannels == 1) dwChannelMask = 0x4; /* 1 channel (mono) = FC */
+ else if (wChannels == 2) dwChannelMask = 0x3; /* 2 channels (stereo) = FL, FR */
+ else if (wChannels == 4) dwChannelMask = 0x33; /* 4 channels (quad) = FL, FR, BL, BR */
+ else if (wChannels == 6) dwChannelMask = 0x3F; /* 6 channels (5.1) = FL, FR, FC, LF, BL, BR */
+ else if (wChannels == 8) dwChannelMask = 0x63F; /* 8 channels (7.1) = FL, FR, FC, LF, BL, BR, SL, SR */
+ }
+
lsx_writew(ft, 22);
lsx_writew(ft, wBitsPerSample); /* No padding in container */
- lsx_writedw(ft, 0); /* Speaker mapping not specified */
+ lsx_writedw(ft, dwChannelMask); /* Speaker mapping is something reasonable */
lsx_writew(ft, wFormatTag);
lsx_writebuf(ft, guids[!strcmp(ft->filetype, "amb")], (size_t)14);
}