vgmstream/src/meta/acm.c

69 lines
2.3 KiB
C

#include "meta.h"
#include "../coding/coding.h"
#include "../coding/acm_decoder_libacm.h"
/* ACM - InterPlay infinity engine games [Planescape: Torment (PC), Baldur's Gate (PC)] */
VGMSTREAM * init_vgmstream_acm(STREAMFILE *streamFile) {
VGMSTREAM * vgmstream = NULL;
int loop_flag = 0, channel_count, sample_rate, num_samples;
int force_channel_number = 0;
acm_codec_data *data = NULL;
/* checks */
/* .acm: plain ACM extension (often but not always paired with .mus, parsed elsewhere)
* .wavc: header id for WAVC sfx (from bigfiles, extensionless) */
if (!check_extensions(streamFile, "acm,wavc"))
goto fail;
if (read_32bitBE(0x00,streamFile) != 0x97280301 && /* header id (music) */
read_32bitBE(0x00,streamFile) != 0x57415643) /* "WAVC" (sfx) */
goto fail;
/* Plain ACM "channels" in the header may be set to 2 for mono voices or 1 for music,
* but actually seem related to ACM rows/cols and have nothing to do with channels.
*
* libacm will set plain ACM (not WAVC) to 2ch unless changes unless changed, but
* only Fallout (PC) seems to use plain ACM for sfx, others are WAVC (which do have channels).
*
* Doesn't look like there is any way to detect mono/stereo, so as a quick hack if
* we have a plain ACM (not WAVC) named .wavc we will force 1ch. */
if (check_extensions(streamFile, "wavc")
&& read_32bitBE(0x00,streamFile) == 0x97280301) {
force_channel_number = 1;
}
/* init decoder */
{
ACMStream *handle;
data = init_acm(streamFile, force_channel_number);
if (!data) goto fail;
handle = data->handle;
channel_count = handle->info.channels;
sample_rate = handle->info.rate;
num_samples = handle->total_values / handle->info.channels;
}
/* build the VGMSTREAM */
vgmstream = allocate_vgmstream(channel_count,loop_flag);
if (!vgmstream) goto fail;
vgmstream->sample_rate = sample_rate;
vgmstream->num_samples = num_samples;
vgmstream->meta_type = meta_ACM;
vgmstream->coding_type = coding_ACM;
vgmstream->layout_type = layout_none;
vgmstream->codec_data = data;
return vgmstream;
fail:
free_acm(data);
close_vgmstream(vgmstream);
return NULL;
}