EA IMA EACS decoder

original patch by Peter Ross

Originally committed as revision 10880 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -276,6 +276,7 @@ OBJS-$(CONFIG_ADPCM_IMA_DK3_DECODER)   += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_DK3_ENCODER)   += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_DK4_DECODER)   += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_DK4_ENCODER)   += adpcm.o
+OBJS-$(CONFIG_ADPCM_IMA_EA_EACS_DECODER) += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_EA_SEAD_DECODER) += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_QT_DECODER)    += adpcm.o
 OBJS-$(CONFIG_ADPCM_IMA_QT_ENCODER)    += adpcm.o

libavcodec/adpcm.c

@@ -31,6 +31,7 @@
  * CD-ROM XA ADPCM codec by BERO
  * EA ADPCM decoder by Robin Kay (komadori@myrealbox.com)
  * EA ADPCM R1/R2/R3 decoder by Peter Ross (pross@xvid.org)
+ * EA IMA EACS decoder by Peter Ross (pross@xvid.org)
  * EA IMA SEAD decoder by Peter Ross (pross@xvid.org)
  * THP ADPCM decoder by Marco Gerards (mgerards@xs4all.nl)
  *
@@ -1138,6 +1139,24 @@ static int adpcm_decode_frame(AVCodecContext *avctx,
             buf_size -= 128;
         }
         break;
+    case CODEC_ID_ADPCM_IMA_EA_EACS:
+        samples_in_chunk = bytestream_get_le32(&src) >> (1-st);
+
+        if (samples_in_chunk > buf_size-4-(8<<st)) {
+            src += buf_size - 4;
+            break;
+        }
+
+        for (i=0; i<=st; i++)
+            c->status[i].step_index = bytestream_get_le32(&src);
+        for (i=0; i<=st; i++)
+            c->status[i].predictor  = bytestream_get_le32(&src);
+
+        for (; samples_in_chunk; samples_in_chunk--, src++) {
+            *samples++ = adpcm_ima_expand_nibble(&c->status[0],  *src>>4,   3);
+            *samples++ = adpcm_ima_expand_nibble(&c->status[st], *src&0x0F, 3);
+        }
+        break;
     case CODEC_ID_ADPCM_IMA_EA_SEAD:
         for (; src < buf+buf_size; src++) {
             *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] >> 4, 6);
@@ -1542,6 +1561,7 @@ ADPCM_CODEC(CODEC_ID_ADPCM_EA, adpcm_ea);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_AMV, adpcm_ima_amv);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4);
+ADPCM_CODEC(CODEC_ID_ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
 ADPCM_CODEC(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg);

libavcodec/allcodecs.c

@@ -254,6 +254,7 @@ void avcodec_register_all(void)
     REGISTER_DECODER (ADPCM_IMA_AMV, adpcm_ima_amv);
     REGISTER_ENCDEC  (ADPCM_IMA_DK3, adpcm_ima_dk3);
     REGISTER_ENCDEC  (ADPCM_IMA_DK4, adpcm_ima_dk4);
+    REGISTER_DECODER (ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs);
     REGISTER_DECODER (ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead);
     REGISTER_ENCDEC  (ADPCM_IMA_QT, adpcm_ima_qt);
     REGISTER_ENCDEC  (ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg);

libavcodec/avcodec.h

@@ -215,6 +215,7 @@ enum CodecID {
     CODEC_ID_ADPCM_EA_R3,
     CODEC_ID_ADPCM_EA_R2,
     CODEC_ID_ADPCM_IMA_EA_SEAD,
+    CODEC_ID_ADPCM_IMA_EA_EACS,
 
     /* AMR */
     CODEC_ID_AMR_NB= 0x12000,

libavformat/electronicarts.c

@@ -201,6 +201,7 @@ static int process_audio_header_eacs(AVFormatContext *s)
         }
         break;
     case 1: ea->audio_codec = CODEC_ID_PCM_MULAW; ea->bytes = 1; break;
+    case 2: ea->audio_codec = CODEC_ID_ADPCM_IMA_EA_EACS; break;
     default:
         av_log (s, AV_LOG_ERROR, "unsupported stream type; audio compression_type=%i\n", compression_type);
     }