[FFmpeg-devel] [PATCH 1/4] avcodec: add ADPCM PSX decoder

Paul B Mahol onemda at gmail.com
Wed Oct 14 23:18:22 CEST 2015


Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 libavcodec/Makefile     |  1 +
 libavcodec/adpcm.c      | 40 ++++++++++++++++++++++++++++++++++++++++
 libavcodec/allcodecs.c  |  1 +
 libavcodec/avcodec.h    |  1 +
 libavcodec/codec_desc.c |  7 +++++++
 libavcodec/utils.c      |  1 +
 6 files changed, 51 insertions(+)

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 8f7493e..1e1e479 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -687,6 +687,7 @@ OBJS-$(CONFIG_ADPCM_IMA_WAV_ENCODER)      += adpcmenc.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_IMA_WS_DECODER)       += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_MS_DECODER)           += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_MS_ENCODER)           += adpcmenc.o adpcm_data.o
+OBJS-$(CONFIG_ADPCM_PSX_DECODER)          += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_SBPRO_2_DECODER)      += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_SBPRO_3_DECODER)      += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_SBPRO_4_DECODER)      += adpcm.o adpcm_data.o
diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c
index ba38041..11eb974 100644
--- a/libavcodec/adpcm.c
+++ b/libavcodec/adpcm.c
@@ -152,6 +152,7 @@ static av_cold int adpcm_decode_init(AVCodecContext * avctx)
         case AV_CODEC_ID_ADPCM_THP_LE:
         case AV_CODEC_ID_ADPCM_AFC:
         case AV_CODEC_ID_ADPCM_DTK:
+        case AV_CODEC_ID_ADPCM_PSX:
             avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
             break;
         case AV_CODEC_ID_ADPCM_IMA_WS:
@@ -665,6 +666,7 @@ static int get_nb_samples(AVCodecContext *avctx, GetByteContext *gb,
         nb_samples = (buf_size / 128) * 224 / ch;
         break;
     case AV_CODEC_ID_ADPCM_DTK:
+    case AV_CODEC_ID_ADPCM_PSX:
         nb_samples = buf_size / (16 * ch) * 28;
         break;
     }
@@ -1548,6 +1550,43 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
                 bytestream2_seek(&gb, 0, SEEK_SET);
         }
         break;
+    case AV_CODEC_ID_ADPCM_PSX:
+        for (channel = 0; channel < avctx->channels; channel++) {
+            samples = samples_p[channel];
+
+            /* Read in every sample for this channel.  */
+            for (i = 0; i < nb_samples / 28; i++) {
+                int filter, shift, flag, byte;
+
+                filter = bytestream2_get_byteu(&gb);
+                shift  = filter & 0xf;
+                filter = filter >> 4;
+                if (filter >= FF_ARRAY_ELEMS(xa_adpcm_table))
+                    return AVERROR_INVALIDDATA;
+                flag   = bytestream2_get_byteu(&gb);
+
+                /* Decode 28 samples.  */
+                for (n = 0; n < 28; n++) {
+                    int sample = 0, scale;
+
+                    if (flag < 0x07) {
+                        if (n & 1) {
+                            scale = sign_extend(byte >> 4, 4);
+                        } else {
+                            byte  = bytestream2_get_byteu(&gb);
+                            scale = sign_extend(byte, 4);
+                        }
+
+                        scale  = scale << 12;
+                        sample = (int)((scale >> shift) + (c->status[channel].sample1 * xa_adpcm_table[filter][0] + c->status[channel].sample2 * xa_adpcm_table[filter][1]) / 64);
+                    }
+                    *samples++ = av_clip_int16(sample);
+                    c->status[channel].sample2 = c->status[channel].sample1;
+                    c->status[channel].sample1 = sample;
+                }
+            }
+        }
+        break;
 
     default:
         return -1;
@@ -1622,6 +1661,7 @@ ADPCM_DECODER(AV_CODEC_ID_ADPCM_IMA_SMJPEG,  sample_fmts_s16,  adpcm_ima_smjpeg,
 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_s16,  adpcm_ms,          "ADPCM Microsoft");
+ADPCM_DECODER(AV_CODEC_ID_ADPCM_PSX,         sample_fmts_s16p, adpcm_psx,         "ADPCM PSX");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_SBPRO_2,     sample_fmts_s16,  adpcm_sbpro_2,     "ADPCM Sound Blaster Pro 2-bit");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_SBPRO_3,     sample_fmts_s16,  adpcm_sbpro_3,     "ADPCM Sound Blaster Pro 2.6-bit");
 ADPCM_DECODER(AV_CODEC_ID_ADPCM_SBPRO_4,     sample_fmts_s16,  adpcm_sbpro_4,     "ADPCM Sound Blaster Pro 4-bit");
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index b506463..d62bec7 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -509,6 +509,7 @@ void avcodec_register_all(void)
     REGISTER_ENCDEC (ADPCM_IMA_WAV,     adpcm_ima_wav);
     REGISTER_DECODER(ADPCM_IMA_WS,      adpcm_ima_ws);
     REGISTER_ENCDEC (ADPCM_MS,          adpcm_ms);
+    REGISTER_DECODER(ADPCM_PSX,         adpcm_psx);
     REGISTER_DECODER(ADPCM_SBPRO_2,     adpcm_sbpro_2);
     REGISTER_DECODER(ADPCM_SBPRO_3,     adpcm_sbpro_3);
     REGISTER_DECODER(ADPCM_SBPRO_4,     adpcm_sbpro_4);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 531286a..18889ec 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -393,6 +393,7 @@ enum AVCodecID {
     AV_CODEC_ID_ADPCM_IMA_RAD,
     AV_CODEC_ID_ADPCM_G726LE,
     AV_CODEC_ID_ADPCM_THP_LE,
+    AV_CODEC_ID_ADPCM_PSX,
 
     /* AMR */
     AV_CODEC_ID_AMR_NB = 0x12000,
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 0817f0c..6979857 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1978,6 +1978,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("LucasArts VIMA audio"),
         .props     = AV_CODEC_PROP_LOSSY,
     },
+    {
+        .id        = AV_CODEC_ID_ADPCM_PSX,
+        .type      = AVMEDIA_TYPE_AUDIO,
+        .name      = "adpcm_psx",
+        .long_name = NULL_IF_CONFIG_SMALL("ADPCM PSX"),
+        .props     = AV_CODEC_PROP_LOSSY,
+    },
 
     /* AMR */
     {
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 0e4f3c0..0ae35ed 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -3063,6 +3063,7 @@ int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
             switch (id) {
             case AV_CODEC_ID_ADPCM_AFC:
                 return frame_bytes / (9 * ch) * 16;
+            case AV_CODEC_ID_ADPCM_PSX:
             case AV_CODEC_ID_ADPCM_DTK:
                 return frame_bytes / (16 * ch) * 28;
             case AV_CODEC_ID_ADPCM_4XM:
-- 
1.9.1



More information about the ffmpeg-devel mailing list