[FFmpeg-devel] [PATCH] avcodec: fix pcm zork decoder
Paul B Mahol
onemda at gmail.com
Fri Feb 14 22:19:38 EET 2020
Fixes #1939
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/Makefile | 2 +-
libavcodec/adpcm.c | 60 +++++++++++++++++++++++++++++++++++++++++
libavcodec/allcodecs.c | 2 +-
libavcodec/codec_desc.c | 4 +--
libavcodec/pcm.c | 9 -------
5 files changed, 64 insertions(+), 13 deletions(-)
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 7825f2741b..b007b1e31e 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -809,7 +809,6 @@ 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-$(CONFIG_ADPCM_ADX_DECODER) += adxdec.o adx.o
@@ -864,6 +863,7 @@ OBJS-$(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_PCM_ZORK_DECODER) += adpcm.o adpcm_data.o
# hardware accelerators
OBJS-$(CONFIG_D3D11VA) += dxva2.o
diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c
index 0cd28431d7..6ede0bbb09 100644
--- a/libavcodec/adpcm.c
+++ b/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_PCM_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_PCM_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_PCM_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_PCM_ZORK, sample_fmts_s16, adpcm_zork, "ADPCM Zork");
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 0ad3338f9a..fcb3645ab1 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -565,7 +565,6 @@ 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;
@@ -629,6 +628,7 @@ 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;
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 621a87cf34..48d0e91370 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1871,8 +1871,8 @@ static const AVCodecDescriptor codec_descriptors[] = {
{
.id = AV_CODEC_ID_PCM_ZORK,
.type = AVMEDIA_TYPE_AUDIO,
- .name = "pcm_zork",
- .long_name = NULL_IF_CONFIG_SMALL("PCM Zork"),
+ .name = "adpcm_zork",
+ .long_name = NULL_IF_CONFIG_SMALL("ADPCM Zork"),
.props = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
},
{
diff --git a/libavcodec/pcm.c b/libavcodec/pcm.c
index 0c4b452b0e..6346510de0 100644
--- a/libavcodec/pcm.c
+++ b/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");
--
2.17.1
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