ffmpeg-2.1.1: move directory

git-svn-id: svn://kolibrios.org@6148 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/ffmpeg/ffmpeg-2.1/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",
+    .long_name      = NULL_IF_CONFIG_SMALL("Westwood Audio (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,
+};