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authorTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
committerTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
commit8992cb1d0d07edc33d274f6d7924ecdf6f83d994 (patch)
tree3a2c86846b7eec8137c1507e623fc7018f13d453 /ffmpeg/libavcodec/ws-snd1.c
parent741fb4b9e135cfb161a749db88713229038577bb (diff)
making act segmenter
Diffstat (limited to 'ffmpeg/libavcodec/ws-snd1.c')
-rw-r--r--ffmpeg/libavcodec/ws-snd1.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/ws-snd1.c b/ffmpeg/libavcodec/ws-snd1.c
new file mode 100644
index 0000000..d27df75
--- /dev/null
+++ b/ffmpeg/libavcodec/ws-snd1.c
@@ -0,0 +1,181 @@
+/*
+ * Westwood SNDx codecs
+ * Copyright (c) 2005 Konstantin Shishkov
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+
+#include "libavutil/channel_layout.h"
+#include "libavutil/common.h"
+#include "libavutil/intreadwrite.h"
+#include "avcodec.h"
+#include "internal.h"
+
+/**
+ * @file
+ * Westwood SNDx codecs
+ *
+ * Reference documents about VQA format and its audio codecs
+ * can be found here:
+ * http://www.multimedia.cx
+ */
+
+static const int8_t ws_adpcm_4bit[] = {
+ -9, -8, -6, -5, -4, -3, -2, -1,
+ 0, 1, 2, 3, 4, 5, 6, 8
+};
+
+static av_cold int ws_snd_decode_init(AVCodecContext *avctx)
+{
+ avctx->channels = 1;
+ avctx->channel_layout = AV_CH_LAYOUT_MONO;
+ avctx->sample_fmt = AV_SAMPLE_FMT_U8;
+
+ return 0;
+}
+
+static int ws_snd_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
+{
+ AVFrame *frame = data;
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+
+ int in_size, out_size, ret;
+ int sample = 128;
+ uint8_t *samples;
+ uint8_t *samples_end;
+
+ if (!buf_size)
+ return 0;
+
+ if (buf_size < 4) {
+ av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
+ return AVERROR(EINVAL);
+ }
+
+ out_size = AV_RL16(&buf[0]);
+ in_size = AV_RL16(&buf[2]);
+ buf += 4;
+
+ if (in_size > buf_size) {
+ av_log(avctx, AV_LOG_ERROR, "Frame data is larger than input buffer\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* get output buffer */
+ frame->nb_samples = out_size;
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+ return ret;
+ samples = frame->data[0];
+ samples_end = samples + out_size;
+
+ if (in_size == out_size) {
+ memcpy(samples, buf, out_size);
+ *got_frame_ptr = 1;
+ return buf_size;
+ }
+
+ while (samples < samples_end && buf - avpkt->data < buf_size) {
+ int code, smp, size;
+ uint8_t count;
+ code = *buf >> 6;
+ count = *buf & 0x3F;
+ buf++;
+
+ /* make sure we don't write past the output buffer */
+ switch (code) {
+ case 0: smp = 4 * (count + 1); break;
+ case 1: smp = 2 * (count + 1); break;
+ case 2: smp = (count & 0x20) ? 1 : count + 1; break;
+ default: smp = count + 1; break;
+ }
+ if (samples_end - samples < smp)
+ break;
+
+ /* make sure we don't read past the input buffer */
+ size = ((code == 2 && (count & 0x20)) || code == 3) ? 0 : count + 1;
+ if ((buf - avpkt->data) + size > buf_size)
+ break;
+
+ switch (code) {
+ case 0: /* ADPCM 2-bit */
+ for (count++; count > 0; count--) {
+ code = *buf++;
+ sample += ( code & 0x3) - 2;
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ sample += ((code >> 2) & 0x3) - 2;
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ sample += ((code >> 4) & 0x3) - 2;
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ sample += (code >> 6) - 2;
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ }
+ break;
+ case 1: /* ADPCM 4-bit */
+ for (count++; count > 0; count--) {
+ code = *buf++;
+ sample += ws_adpcm_4bit[code & 0xF];
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ sample += ws_adpcm_4bit[code >> 4];
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ }
+ break;
+ case 2: /* no compression */
+ if (count & 0x20) { /* big delta */
+ int8_t t;
+ t = count;
+ t <<= 3;
+ sample += t >> 3;
+ sample = av_clip_uint8(sample);
+ *samples++ = sample;
+ } else { /* copy */
+ memcpy(samples, buf, smp);
+ samples += smp;
+ buf += smp;
+ sample = buf[-1];
+ }
+ break;
+ default: /* run */
+ memset(samples, sample, smp);
+ samples += smp;
+ }
+ }
+
+ frame->nb_samples = samples - frame->data[0];
+ *got_frame_ptr = 1;
+
+ return buf_size;
+}
+
+AVCodec ff_ws_snd1_decoder = {
+ .name = "ws_snd1",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_WESTWOOD_SND1,
+ .init = ws_snd_decode_init,
+ .decode = ws_snd_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Westwood Audio (SND1)"),
+};