avcodec: add decoder for High Voltage Software's ALP ADPCM

[ffmpeg] / libavcodec / adpcm.c

diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c
index 5f152ee6ef793cf8a411463a078fb114ff5135e7..c69cac337914ed30634fc60633993f03e8e06f67 100644 (file)
--- a/libavcodec/adpcm.c
+++ b/libavcodec/adpcm.c
@@ -15,6 +15,7 @@
  * Argonaut Games ADPCM decoder by Zane van Iperen (zane@zanevaniperen.com)
  * Simon & Schuster Interactive ADPCM decoder by Zane van Iperen (zane@zanevaniperen.com)
  * Ubisoft ADPCM decoder by Zane van Iperen (zane@zanevaniperen.com)
+ * High Voltage Software ALP decoder by Zane van Iperen (zane@zanevaniperen.com)
  *
  * This file is part of FFmpeg.
  *
@@ -280,6 +281,29 @@ static inline int16_t adpcm_ima_expand_nibble(ADPCMChannelStatus *c, int8_t nibb
     return (int16_t)c->predictor;
 }
 
+static inline int16_t adpcm_ima_alp_expand_nibble(ADPCMChannelStatus *c, int8_t nibble, int shift)
+{
+    int step_index;
+    int predictor;
+    int sign, delta, diff, step;
+
+    step = ff_adpcm_step_table[c->step_index];
+    step_index = c->step_index + ff_adpcm_index_table[(unsigned)nibble];
+    step_index = av_clip(step_index, 0, 88);
+
+    sign = nibble & 8;
+    delta = nibble & 7;
+    diff = (delta * step) >> shift;
+    predictor = c->predictor;
+    if (sign) predictor -= diff;
+    else predictor += diff;
+
+    c->predictor = av_clip_int16(predictor);
+    c->step_index = step_index;
+
+    return (int16_t)c->predictor;
+}
+
 static inline int16_t adpcm_ima_wav_expand_nibble(ADPCMChannelStatus *c, GetBitContext *gb, int bps)
 {
     int nibble, step_index, predictor, sign, delta, diff, step, shift;
@@ -675,6 +699,7 @@ static int get_nb_samples(AVCodecContext *avctx, GetByteContext *gb,
     case AV_CODEC_ID_ADPCM_AICA:
     case AV_CODEC_ID_ADPCM_IMA_SSI:
     case AV_CODEC_ID_ADPCM_IMA_APM:
+    case AV_CODEC_ID_ADPCM_IMA_ALP:
         nb_samples = buf_size * 2 / ch;
         break;
     }
@@ -1247,6 +1272,16 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
             samples += avctx->channels;
         }
         break;
+    case AV_CODEC_ID_ADPCM_IMA_ALP:
+        for (n = nb_samples / 2; n > 0; n--) {
+            for (channel = 0; channel < avctx->channels; channel++) {
+                int v = bytestream2_get_byteu(&gb);
+                *samples++  = adpcm_ima_alp_expand_nibble(&c->status[channel], v >> 4  , 2);
+                samples[st] = adpcm_ima_alp_expand_nibble(&c->status[channel], v & 0x0F, 2);
+            }
+            samples += avctx->channels;
+        }
+        break;
     case AV_CODEC_ID_ADPCM_IMA_OKI:
         while (bytestream2_get_bytes_left(&gb) > 0) {
             int v = bytestream2_get_byteu(&gb);
@@ -1997,6 +2032,7 @@ ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_QT,      sample_fmts_s16p, adpcm_ima_qt,
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_RAD,     sample_fmts_s16,  adpcm_ima_rad,     "ADPCM IMA Radical");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_SSI,     sample_fmts_s16,  adpcm_ima_ssi,     "ADPCM IMA Simon & Schuster Interactive");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_SMJPEG,  sample_fmts_s16,  adpcm_ima_smjpeg,  "ADPCM IMA Loki SDL MJPEG");
+ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_ALP,     sample_fmts_s16,  adpcm_ima_alp,     "ADPCM IMA High Voltage Software ALP");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_WAV,     sample_fmts_s16p, adpcm_ima_wav,     "ADPCM IMA WAV");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_WS,      sample_fmts_both, adpcm_ima_ws,      "ADPCM IMA Westwood");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_MS,          sample_fmts_both, adpcm_ms,          "ADPCM Microsoft");