* EA IMA EACS decoder by Peter Ross (pross@xvid.org)
* EA IMA SEAD decoder by Peter Ross (pross@xvid.org)
* EA ADPCM XAS decoder by Peter Ross (pross@xvid.org)
+ * MAXIS EA ADPCM decoder by Robert Marston (rmarston@gmail.com)
* THP ADPCM decoder by Marco Gerards (mgerards@xs4all.nl)
*
* Features and limitations:
static av_cold int adpcm_decode_init(AVCodecContext * avctx)
{
ADPCMContext *c = avctx->priv_data;
- unsigned int max_channels = 2;
+ unsigned int max_channels = 2, channel;
switch(avctx->codec->id) {
case CODEC_ID_ADPCM_EA_R1:
int32_t coeff1l, coeff2l, coeff1r, coeff2r;
uint8_t shift_left, shift_right;
int count1, count2;
+ int coeff[2][2], shift[2];//used in EA MAXIS ADPCM
if (!buf_size)
return 0;
}
}
break;
+ case CODEC_ID_ADPCM_EA_MAXIS_XA:
+ for(channel = 0; channel < avctx->channels; channel++) {
+ for (i=0; i<2; i++)
+ coeff[channel][i] = ea_adpcm_table[(*src >> 4) + 4*i];
+ shift[channel] = (*src & 0x0F) + 8;
+ src++;
+ }
+ for (count1 = 0; count1 < (buf_size - avctx->channels) / avctx->channels; count1++) {
+ for(i = 4; i >= 0; i-=4) { /* Pairwise samples LL RR (st) or LL LL (mono) */
+ for(channel = 0; channel < avctx->channels; channel++) {
+ int32_t sample = (int32_t)(((*(src+channel) >> i) & 0x0F) << 0x1C) >> shift[channel];
+ sample = (sample +
+ c->status[channel].sample1 * coeff[channel][0] +
+ c->status[channel].sample2 * coeff[channel][1] + 0x80) >> 8;
+ c->status[channel].sample2 = c->status[channel].sample1;
+ c->status[channel].sample1 = av_clip_int16(sample);
+ *samples++ = c->status[channel].sample1;
+ }
+ }
+ src+=avctx->channels;
+ }
+ break;
case CODEC_ID_ADPCM_EA_R1:
case CODEC_ID_ADPCM_EA_R2:
case CODEC_ID_ADPCM_EA_R3: {
ADPCM_DECODER(CODEC_ID_ADPCM_4XM, adpcm_4xm);
ADPCM_DECODER(CODEC_ID_ADPCM_CT, adpcm_ct);
ADPCM_DECODER(CODEC_ID_ADPCM_EA, adpcm_ea);
+ADPCM_DECODER(CODEC_ID_ADPCM_EA_MAXIS_XA, adpcm_ea_maxis_xa);
ADPCM_DECODER(CODEC_ID_ADPCM_EA_R1, adpcm_ea_r1);
ADPCM_DECODER(CODEC_ID_ADPCM_EA_R2, adpcm_ea_r2);
ADPCM_DECODER(CODEC_ID_ADPCM_EA_R3, adpcm_ea_r3);
--- /dev/null
+/*
+ * Maxis XA (.xa) File Demuxer
+ * Copyright (c) 2008 Robert Marston
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file xa.c
+ * Maxis XA File Demuxer
+ * by Robert Marston (rmarston@gmail.com)
+ * for more information on the XA audio format see
+ * http://wiki.multimedia.cx/index.php?title=Maxis_XA
+ */
+
+#include "avformat.h"
+
+#define XA00_TAG MKTAG('X', 'A', 0, 0)
+#define XAI0_TAG MKTAG('X', 'A', 'I', 0)
+#define XAJ0_TAG MKTAG('X', 'A', 'J', 0)
+
+typedef struct MaxisXADemuxContext {
+ uint32_t out_size;
+ uint32_t sent_bytes;
+ uint32_t audio_frame_counter;
+} MaxisXADemuxContext;
+
+static int xa_probe(AVProbeData *p)
+{
+ switch(AV_RL32(p->buf)) {
+ case XA00_TAG:
+ case XAI0_TAG:
+ case XAJ0_TAG:
+ return AVPROBE_SCORE_MAX;
+ }
+ return 0;
+}
+
+static int xa_read_header(AVFormatContext *s,
+ AVFormatParameters *ap)
+{
+ MaxisXADemuxContext *xa = s->priv_data;
+ ByteIOContext *pb = s->pb;
+ AVStream *st;
+
+ /*Set up the XA Audio Decoder*/
+ st = av_new_stream(s, 0);
+ if (!st)
+ return AVERROR(ENOMEM);
+
+ st->codec->codec_type = CODEC_TYPE_AUDIO;
+ st->codec->codec_id = CODEC_ID_ADPCM_EA_MAXIS_XA;
+ url_fskip(pb, 4); /* Skip the XA ID */
+ xa->out_size = get_le32(pb);
+ url_fskip(pb, 2); /* Skip the tag */
+ st->codec->channels = get_le16(pb);
+ st->codec->sample_rate = get_le32(pb);
+ /* Value in file is average byte rate*/
+ st->codec->bit_rate = get_le32(pb) * 8;
+ st->codec->block_align = get_le16(pb);
+ st->codec->bits_per_sample = get_le16(pb);
+
+ av_set_pts_info(st, 64, 1, st->codec->sample_rate);
+
+ return 0;
+}
+
+static int xa_read_packet(AVFormatContext *s,
+ AVPacket *pkt)
+{
+ MaxisXADemuxContext *xa = s->priv_data;
+ AVStream *st = s->streams[0];
+ ByteIOContext *pb = s->pb;
+ unsigned int packet_size;
+ int ret;
+
+ if(xa->sent_bytes > xa->out_size)
+ return AVERROR(EIO);
+ /* 1 byte header and 14 bytes worth of samples * number channels per block */
+ packet_size = 15*st->codec->channels;
+
+ ret = av_get_packet(pb, pkt, packet_size);
+ if(ret != packet_size)
+ return AVERROR(EIO);
+
+ pkt->stream_index = st->index;
+ xa->sent_bytes += packet_size;
+ pkt->pts = xa->audio_frame_counter;
+ /* 14 bytes Samples per channel with 2 samples per byte */
+ xa->audio_frame_counter += 28 * st->codec->channels;
+
+ return ret;
+}
+
+AVInputFormat xa_demuxer = {
+ "xa",
+ "Maxis XA File Format",
+ sizeof(MaxisXADemuxContext),
+ xa_probe,
+ xa_read_header,
+ xa_read_packet,
+};