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Diffstat (limited to 'lib/vgmstream/src/coding/nwa_decoder.c')
-rw-r--r--lib/vgmstream/src/coding/nwa_decoder.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/lib/vgmstream/src/coding/nwa_decoder.c b/lib/vgmstream/src/coding/nwa_decoder.c
new file mode 100644
index 0000000000..a568007859
--- /dev/null
+++ b/lib/vgmstream/src/coding/nwa_decoder.c
@@ -0,0 +1,352 @@
+/* originally from nwatowav.cc 2007.7.28 version, which read: */
+/*
+ * Copyright 2001-2007 jagarl / Kazunori Ueno <jagarl@creator.club.ne.jp>
+ * All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted.
+ *
+ * このプログラムの作者は jagarl です。
+ *
+ * このプログラム、及びコンパイルによって生成したバイナリは
+ * プログラムを変更する、しないにかかわらず再配布可能です。
+ * その際、上記 Copyright 表示を保持するなどの条件は課しま
+ * せん。対応が面倒なのでバグ報告を除き、メールで連絡をする
+ * などの必要もありません。ソースの一部を流用することを含め、
+ * ご自由にお使いください。
+ *
+ * THIS SOFTWARE IS PROVIDED BY KAZUNORI 'jagarl' UENO ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL KAZUNORI UENO BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <stdlib.h>
+#include "nwa_decoder.h"
+
+/* can serve up 8 bits at a time */
+static int
+getbits (STREAMFILE *file, off_t *offset, int *shift, int bits)
+{
+ int ret;
+ if (*shift > 8)
+ {
+ ++*offset;
+ *shift -= 8;
+ }
+ ret = read_16bitLE(*offset,file) >> *shift;
+ *shift += bits;
+ return ret & ((1 << bits) - 1); /* mask */
+}
+
+NWAData *
+open_nwa (STREAMFILE * streamFile, const char *filename)
+{
+ int i;
+ NWAData * const nwa = malloc(sizeof(NWAData));
+ if (!nwa) goto fail;
+
+ nwa->channels = read_16bitLE(0x00,streamFile);
+ nwa->bps = read_16bitLE(0x02,streamFile);
+ nwa->freq = read_32bitLE(0x04,streamFile);
+ nwa->complevel = read_32bitLE(0x08,streamFile);
+ nwa->blocks = read_32bitLE(0x10,streamFile);
+ nwa->datasize = read_32bitLE(0x14,streamFile);
+ nwa->compdatasize = read_32bitLE(0x18,streamFile);
+ nwa->samplecount = read_32bitLE(0x1c,streamFile);
+ nwa->blocksize = read_32bitLE(0x20,streamFile);
+ nwa->restsize = read_32bitLE(0x24,streamFile);
+ nwa->offsets = NULL;
+ nwa->buffer = NULL;
+ nwa->buffer_readpos = NULL;
+ nwa->file = NULL;
+
+ /* PCM not handled here */
+ if (nwa->complevel < 0 || nwa->complevel > 5) goto fail;
+
+ if (nwa->channels != 1 && nwa->channels != 2) goto fail;
+
+ if (nwa->bps != 8 && nwa->bps != 16) goto fail;
+
+ if (nwa->blocks <= 0) goto fail;
+
+ if (nwa->compdatasize == 0
+ || get_streamfile_size(streamFile) != nwa->compdatasize) goto fail;
+
+ if (nwa->datasize != nwa->samplecount * (nwa->bps/8)) goto fail;
+
+ if (nwa->samplecount !=
+ (nwa->blocks-1) * nwa->blocksize + nwa->restsize) goto fail;
+
+ nwa->offsets = malloc(sizeof(off_t)*nwa->blocks);
+ if (!nwa->offsets) goto fail;
+
+ for (i = 0; i < nwa->blocks; i++)
+ {
+ int32_t o = read_32bitLE(0x2c+i*4,streamFile);
+ if (o < 0) goto fail;
+ nwa->offsets[i] = o;
+ }
+
+ if (nwa->offsets[nwa->blocks-1] >= nwa->compdatasize) goto fail;
+
+ if (nwa->restsize > nwa->blocksize) nwa->buffer =
+ malloc(sizeof(sample)*nwa->restsize);
+ else nwa->buffer =
+ malloc(sizeof(sample)*nwa->blocksize);
+ if (nwa->buffer == NULL) goto fail;
+
+ nwa->buffer_readpos = nwa->buffer;
+
+ nwa->samples_in_buffer = 0;
+
+ nwa->curblock = 0;
+
+ /* if we got this far, it's probably safe */
+ nwa->file = streamFile->open(streamFile,filename,STREAMFILE_DEFAULT_BUFFER_SIZE);
+ if (!nwa->file) goto fail;
+
+ return nwa;
+fail:
+ if (nwa)
+ {
+ close_nwa(nwa);
+ free(nwa);
+ }
+
+ return NULL;
+}
+
+void
+close_nwa(NWAData * nwa)
+{
+ if (!nwa) return;
+
+ if (nwa->offsets)
+ free (nwa->offsets);
+ nwa->offsets = NULL;
+ if (nwa->buffer)
+ free (nwa->buffer);
+ nwa->buffer = NULL;
+ if (nwa->file)
+ close_streamfile (nwa->file);
+ nwa->file = NULL;
+ free(nwa);
+}
+
+void
+reset_nwa(NWAData *nwa)
+{
+ nwa->curblock = 0;
+ nwa->buffer_readpos = nwa->buffer;
+ nwa->samples_in_buffer = 0;
+}
+
+static int use_runlength(NWAData *nwa)
+{
+ if (nwa->channels == 2 && nwa->bps == 16 && nwa->complevel == 2)
+ {
+ /* sw2 */
+ return 0;
+ }
+ if (nwa->complevel == 5)
+ {
+ if (nwa->channels == 2) return 0; /* BGM*.nwa in Little Busters! */
+ return 1; /* Tomoyo After (.nwk koe file) */
+ }
+ return 0;
+}
+
+static void
+nwa_decode_block(NWAData *nwa)
+{
+ /* 今回読み込む／デコードするデータの大きさを得る */
+ int curblocksize, curcompsize;
+ if (nwa->curblock != nwa->blocks - 1)
+ {
+ curblocksize = nwa->blocksize * (nwa->bps / 8);
+ curcompsize = nwa->offsets[nwa->curblock + 1] - nwa->offsets[nwa->curblock];
+ }
+ else
+ {
+ curblocksize = nwa->restsize * (nwa->bps / 8);
+ curcompsize = nwa->blocksize * (nwa->bps / 8) * 2;
+ }
+
+ nwa->samples_in_buffer = 0;
+ nwa->buffer_readpos = nwa->buffer;
+
+ {
+ sample d[2];
+ int i;
+ int shift = 0;
+ off_t offset = nwa->offsets[nwa->curblock];
+ int dsize = curblocksize / (nwa->bps / 8);
+ int flip_flag = 0; /* stereo 用 */
+ int runlength = 0;
+
+ /* read initial sample value */
+ for (i=0;i<nwa->channels;i++)
+ {
+ if (nwa->bps == 8) { d[i] = read_8bit(offset,nwa->file); }
+ else /* bps == 16 */
+ {
+ d[i] = read_16bitLE(offset,nwa->file);
+ offset += 2;
+ }
+ }
+
+ for (i = 0; i < dsize; i++)
+ {
+ if (runlength == 0)
+ { /* コピーループ中でないならデータ読み込み */
+ int type = getbits(nwa->file, &offset, &shift, 3);
+ /* type により分岐：0, 1-6, 7 */
+ if (type == 7)
+ {
+ /* 7 : 大きな差分 */
+ /* RunLength() 有効時（CompLevel==5, 音声ファイル) では無効 */
+ if (getbits(nwa->file, &offset, &shift, 1) == 1)
+ {
+ d[flip_flag] = 0; /* 未使用 */
+ }
+ else
+ {
+ int BITS, SHIFT;
+ if (nwa->complevel >= 3)
+ {
+ BITS = 8;
+ SHIFT = 9;
+ }
+ else
+ {
+ BITS = 8 - nwa->complevel;
+ SHIFT = 2 + 7 + nwa->complevel;
+ }
+ {
+ const int MASK1 = (1 << (BITS - 1));
+ const int MASK2 = (1 << (BITS - 1)) - 1;
+ int b = getbits(nwa->file, &offset, &shift, BITS);
+ if (b & MASK1)
+ d[flip_flag] -= (b & MASK2) << SHIFT;
+ else
+ d[flip_flag] += (b & MASK2) << SHIFT;
+ }
+ }
+ }
+ else if (type != 0)
+ {
+ /* 1-6 : 通常の差分 */
+ int BITS, SHIFT;
+ if (nwa->complevel >= 3)
+ {
+ BITS = nwa->complevel + 3;
+ SHIFT = 1 + type;
+ }
+ else
+ {
+ BITS = 5 - nwa->complevel;
+ SHIFT = 2 + type + nwa->complevel;
+ }
+ {
+ const int MASK1 = (1 << (BITS - 1));
+ const int MASK2 = (1 << (BITS - 1)) - 1;
+ int b = getbits(nwa->file, &offset, &shift, BITS);
+ if (b & MASK1)
+ d[flip_flag] -= (b & MASK2) << SHIFT;
+ else
+ d[flip_flag] += (b & MASK2) << SHIFT;
+ }
+ }
+ else
+ { /* type == 0 */
+ /* ランレングス圧縮なしの場合はなにもしない */
+ if (use_runlength(nwa))
+ {
+ /* ランレングス圧縮ありの場合 */
+ runlength = getbits(nwa->file, &offset, &shift, 1);
+ if (runlength == 1)
+ {
+ runlength = getbits(nwa->file, &offset, &shift, 2);
+ if (runlength == 3)
+ {
+ runlength = getbits(nwa->file, &offset, &shift, 8);
+ }
+ }
+ }
+ }
+ }
+ else
+ {
+ runlength--;
+ }
+ if (nwa->bps == 8)
+ {
+ nwa->buffer[i] = d[flip_flag]*0x100;
+ }
+ else
+ {
+ nwa->buffer[i] = d[flip_flag];
+ }
+ nwa->samples_in_buffer++;
+ if (nwa->channels == 2)
+ flip_flag ^= 1; /* channel 切り替え */
+ }
+ }
+
+ nwa->curblock++;
+ return;
+}
+
+void
+seek_nwa(NWAData *nwa, int32_t seekpos)
+{
+ int dest_block = seekpos/(nwa->blocksize/nwa->channels);
+ int32_t remainder = seekpos%(nwa->blocksize/nwa->channels);
+
+ nwa->curblock = dest_block;
+
+ nwa_decode_block(nwa);
+
+ nwa->buffer_readpos = nwa->buffer + remainder*nwa->channels;
+ nwa->samples_in_buffer -= remainder*nwa->channels;
+}
+
+/* interface to vgmstream */
+void
+decode_nwa(NWAData *nwa, sample *outbuf,
+ int32_t samples_to_do)
+{
+ while (samples_to_do > 0)
+ {
+ int32_t samples_to_read;
+
+ if (nwa->samples_in_buffer > 0)
+ {
+ samples_to_read = nwa->samples_in_buffer/nwa->channels;
+ if (samples_to_read > samples_to_do)
+ samples_to_read = samples_to_do;
+
+ memcpy(outbuf,nwa->buffer_readpos,
+ sizeof(sample)*samples_to_read*nwa->channels);
+
+ nwa->buffer_readpos += samples_to_read*nwa->channels;
+ nwa->samples_in_buffer -= samples_to_read*nwa->channels;
+ outbuf += samples_to_read*nwa->channels;
+ samples_to_do -= samples_to_read;
+ }
+ else
+ {
+ nwa_decode_block(nwa);
+ }
+ }
+}
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