avcodec: fix pcm zork decoder

Fixes #1939

libavcodec/Makefile

@@ -810,7 +810,6 @@ OBJS-$(CONFIG_PCM_U32LE_DECODER)          += pcm.o
 OBJS-$(CONFIG_PCM_U32LE_ENCODER)          += pcm.o
 OBJS-$(CONFIG_PCM_VIDC_DECODER)           += pcm.o
 OBJS-$(CONFIG_PCM_VIDC_ENCODER)           += pcm.o
-OBJS-$(CONFIG_PCM_ZORK_DECODER)           += pcm.o
 
 OBJS-$(CONFIG_ADPCM_4XM_DECODER)          += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_ADX_DECODER)          += adxdec.o adx.o
@@ -865,6 +864,7 @@ OBJS-$(CONFIG_ADPCM_VIMA_DECODER)         += vima.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_XA_DECODER)           += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER)       += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER)       += adpcmenc.o adpcm_data.o
+OBJS-$(CONFIG_ADPCM_ZORK_DECODER)         += adpcm.o adpcm_data.o
 
 # hardware accelerators
 OBJS-$(CONFIG_D3D11VA)                    += dxva2.o

libavcodec/adpcm.c

@@ -83,6 +83,10 @@ static const int8_t swf_index_tables[4][16] = {
     /*5*/ { -1, -1, -1, -1, -1, -1, -1, -1, 1, 2, 4, 6, 8, 10, 13, 16 }
 };
 
+static const int8_t zork_index_table[8] = {
+    -1, -1, -1, 1, 4, 7, 10, 12,
+};
+
 /* end of tables */
 
 typedef struct ADPCMDecodeContext {
@@ -154,6 +158,10 @@ static av_cold int adpcm_decode_init(AVCodecContext * avctx)
         if (avctx->bits_per_coded_sample != 4)
             return AVERROR_INVALIDDATA;
         break;
+    case AV_CODEC_ID_ADPCM_ZORK:
+        if (avctx->bits_per_coded_sample != 8)
+            return AVERROR_INVALIDDATA;
+        break;
     default:
         break;
     }
@@ -416,6 +424,41 @@ static inline int16_t adpcm_mtaf_expand_nibble(ADPCMChannelStatus *c, uint8_t ni
     return c->predictor;
 }
 
+static inline int16_t adpcm_zork_expand_nibble(ADPCMChannelStatus *c, uint8_t nibble)
+{
+    int16_t index = c->step_index;
+    uint32_t lookup_sample = ff_adpcm_step_table[index];
+    int32_t sample = 0;
+
+    if (nibble & 0x40)
+        sample += lookup_sample;
+    if (nibble & 0x20)
+        sample += lookup_sample >> 1;
+    if (nibble & 0x10)
+        sample += lookup_sample >> 2;
+    if (nibble & 0x08)
+        sample += lookup_sample >> 3;
+    if (nibble & 0x04)
+        sample += lookup_sample >> 4;
+    if (nibble & 0x02)
+        sample += lookup_sample >> 5;
+    if (nibble & 0x01)
+        sample += lookup_sample >> 6;
+    if (nibble & 0x80)
+        sample = -sample;
+
+    sample += c->predictor;
+    sample = av_clip_int16(sample);
+
+    index += zork_index_table[(nibble >> 4) & 7];
+    index = av_clip(index, 0, 88);
+
+    c->predictor = sample;
+    c->step_index = index;
+
+    return sample;
+}
+
 static int xa_decode(AVCodecContext *avctx, int16_t *out0, int16_t *out1,
                      const uint8_t *in, ADPCMChannelStatus *left,
                      ADPCMChannelStatus *right, int channels, int sample_offset)
@@ -780,6 +823,9 @@ static int get_nb_samples(AVCodecContext *avctx, GetByteContext *gb,
     case AV_CODEC_ID_ADPCM_PSX:
         nb_samples = buf_size / (16 * ch) * 28;
         break;
+    case AV_CODEC_ID_ADPCM_ZORK:
+        nb_samples = buf_size / ch;
+        break;
     }
 
     /* validate coded sample count */
@@ -1842,6 +1888,19 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
             }
         }
         break;
+    case AV_CODEC_ID_ADPCM_ZORK:
+        if (!c->has_status) {
+            for (channel = 0; channel < avctx->channels; channel++) {
+                c->status[channel].predictor  = 0;
+                c->status[channel].step_index = 0;
+            }
+            c->has_status = 1;
+        }
+        for (n = 0; n < nb_samples * avctx->channels; n++) {
+            int v = bytestream2_get_byteu(&gb);
+            *samples++ = adpcm_zork_expand_nibble(&c->status[n % avctx->channels], v);
+        }
+        break;
     default:
         av_assert0(0); // unsupported codec_id should not happen
     }
@@ -1930,3 +1989,4 @@ ADPCM_DECODER(AV_CODEC_ID_ADPCM_THP_LE,      sample_fmts_s16p, adpcm_thp_le,
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_THP,         sample_fmts_s16p, adpcm_thp,         "ADPCM Nintendo THP");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_XA,          sample_fmts_s16p, adpcm_xa,          "ADPCM CDROM XA");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_YAMAHA,      sample_fmts_s16,  adpcm_yamaha,      "ADPCM Yamaha");
+ADPCM_DECODER(AV_CODEC_ID_ADPCM_ZORK,        sample_fmts_s16,  adpcm_zork,        "ADPCM Zork");

libavcodec/allcodecs.c

@@ -566,7 +566,6 @@ extern AVCodec ff_pcm_u32le_encoder;
 extern AVCodec ff_pcm_u32le_decoder;
 extern AVCodec ff_pcm_vidc_encoder;
 extern AVCodec ff_pcm_vidc_decoder;
-extern AVCodec ff_pcm_zork_decoder;
 
 /* DPCM codecs */
 extern AVCodec ff_gremlin_dpcm_decoder;
@@ -630,6 +629,7 @@ extern AVCodec ff_adpcm_vima_decoder;
 extern AVCodec ff_adpcm_xa_decoder;
 extern AVCodec ff_adpcm_yamaha_encoder;
 extern AVCodec ff_adpcm_yamaha_decoder;
+extern AVCodec ff_adpcm_zork_decoder;
 
 /* subtitles */
 extern AVCodec ff_ssa_encoder;

libavcodec/avcodec.h

@@ -548,6 +548,7 @@ enum AVCodecID {
     AV_CODEC_ID_ADPCM_AGM,
     AV_CODEC_ID_ADPCM_ARGO,
     AV_CODEC_ID_ADPCM_IMA_SSI,
+    AV_CODEC_ID_ADPCM_ZORK,
 
     /* AMR */
     AV_CODEC_ID_AMR_NB = 0x12000,

libavcodec/codec_desc.c

@@ -1875,13 +1875,6 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("PCM D-Cinema audio signed 24-bit"),
         .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
     },
-    {
-        .id        = AV_CODEC_ID_PCM_ZORK,
-        .type      = AVMEDIA_TYPE_AUDIO,
-        .name      = "pcm_zork",
-        .long_name = NULL_IF_CONFIG_SMALL("PCM Zork"),
-        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
-    },
     {
         .id        = AV_CODEC_ID_PCM_S16LE_PLANAR,
         .type      = AVMEDIA_TYPE_AUDIO,
@@ -2318,6 +2311,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("ADPCM IMA Simon & Schuster Interactive"),
         .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
     },
+    {
+        .id        = AV_CODEC_ID_ADPCM_ZORK,
+        .type      = AVMEDIA_TYPE_AUDIO,
+        .name      = "adpcm_zork",
+        .long_name = NULL_IF_CONFIG_SMALL("ADPCM Zork"),
+        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
+    },
 
     /* AMR */
     {

libavcodec/pcm.c

@@ -491,14 +491,6 @@ static int pcm_decode_frame(AVCodecContext *avctx, void *data,
             bytestream_get_buffer(&src, samples, n * sample_size);
         }
         break;
-    case AV_CODEC_ID_PCM_ZORK:
-        for (; n > 0; n--) {
-            int v = *src++;
-            if (v < 128)
-                v = 128 - v;
-            *samples++ = v;
-        }
-        break;
     case AV_CODEC_ID_PCM_ALAW:
     case AV_CODEC_ID_PCM_MULAW:
     case AV_CODEC_ID_PCM_VIDC:
@@ -626,7 +618,6 @@ PCM_CODEC  (PCM_U24BE,        AV_SAMPLE_FMT_S32, pcm_u24be,        "PCM unsigned
 PCM_CODEC  (PCM_U24LE,        AV_SAMPLE_FMT_S32, pcm_u24le,        "PCM unsigned 24-bit little-endian");
 PCM_CODEC  (PCM_U32BE,        AV_SAMPLE_FMT_S32, pcm_u32be,        "PCM unsigned 32-bit big-endian");
 PCM_CODEC  (PCM_U32LE,        AV_SAMPLE_FMT_S32, pcm_u32le,        "PCM unsigned 32-bit little-endian");
-PCM_DECODER(PCM_ZORK,         AV_SAMPLE_FMT_U8,  pcm_zork,         "PCM Zork");
 PCM_CODEC  (PCM_S64BE,        AV_SAMPLE_FMT_S64, pcm_s64be,        "PCM signed 64-bit big-endian");
 PCM_CODEC  (PCM_S64LE,        AV_SAMPLE_FMT_S64, pcm_s64le,        "PCM signed 64-bit little-endian");
 PCM_CODEC  (PCM_VIDC,         AV_SAMPLE_FMT_S16, pcm_vidc,         "PCM Archimedes VIDC");

libavcodec/utils.c

@@ -1474,7 +1474,6 @@ int av_get_exact_bits_per_sample(enum AVCodecID codec_id)
     case AV_CODEC_ID_PCM_S8:
     case AV_CODEC_ID_PCM_S8_PLANAR:
     case AV_CODEC_ID_PCM_U8:
-    case AV_CODEC_ID_PCM_ZORK:
     case AV_CODEC_ID_SDX2_DPCM:
         return 8;
     case AV_CODEC_ID_PCM_S16BE:

libavcodec/version.h

@@ -28,7 +28,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR  58
-#define LIBAVCODEC_VERSION_MINOR  69
+#define LIBAVCODEC_VERSION_MINOR  70
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

libavformat/riff.c

@@ -516,7 +516,7 @@ const AVCodecTag ff_codec_wav_tags[] = {
     { AV_CODEC_ID_ADPCM_IMA_OKI,   0x0010 },
     { AV_CODEC_ID_ADPCM_IMA_WAV,   0x0011 },
     /* must come after adpcm_ima_wav in this list */
-    { AV_CODEC_ID_PCM_ZORK,        0x0011 },
+    { AV_CODEC_ID_ADPCM_ZORK,      0x0011 },
     { AV_CODEC_ID_ADPCM_IMA_OKI,   0x0017 },
     { AV_CODEC_ID_ADPCM_YAMAHA,    0x0020 },
     { AV_CODEC_ID_TRUESPEECH,      0x0022 },

libavformat/riffdec.c

@@ -202,7 +202,7 @@ enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
         id = ff_get_pcm_codec_id(bps, 1, 0,  0);
 
     if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
-        id = AV_CODEC_ID_PCM_ZORK;
+        id = AV_CODEC_ID_ADPCM_ZORK;
     return id;
 }