RedSpark demuxer

Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 157 insertions, 0 deletions

diff --git a/libavformat/redspark.c b/libavformat/redspark.c
new file mode 100644
index 0000000000..f98c1156ed
--- /dev/null
+++ b/libavformat/redspark.c
@@ -0,0 +1,157 @@
+/*
+ * RedSpark demuxer
+ * Copyright (c) 2013 James Almer
+ *
+ * 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
+ */
+
+#include "libavcodec/bytestream.h"
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "avio.h"
+#include "internal.h"
+
+#define HEADER_SIZE 4096
+
+typedef struct RedSparkContext {
+    int         samples_count;
+} RedSparkContext;
+
+static int redspark_probe(AVProbeData *p)
+{
+    uint32_t key, data;
+    uint8_t header[8];
+
+    /* Decrypt first 8 bytes of the header */
+    data = AV_RB32(p->buf);
+    data = data ^ (key = data ^ 0x52656453);
+    AV_WB32(header, data);
+    key = (key << 11) | (key >> 21);
+
+    data = AV_RB32(p->buf + 4) ^ (((key << 3) | (key >> 29)) + key);
+    AV_WB32(header + 4, data);
+
+    if (AV_RB64(header) == AV_RB64("RedSpark"))
+        return AVPROBE_SCORE_MAX;
+
+    return 0;
+}
+
+static int redspark_read_header(AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    RedSparkContext *redspark = s->priv_data;
+    AVCodecContext *codec;
+    GetByteContext gbc;
+    int i, coef_off;
+    uint32_t key, data;
+    uint8_t *header, *pbc;
+    AVStream *st;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+    codec = st->codec;
+
+    header = av_malloc(HEADER_SIZE);
+    if (!header)
+        return AVERROR(ENOMEM);
+    pbc = header;
+
+    /* Decrypt header */
+    data = avio_rb32(pb);
+    data = data ^ (key = data ^ 0x52656453);
+    bytestream_put_be32(&pbc, data);
+    key = (key << 11) | (key >> 21);
+
+    for (i = 4; i < HEADER_SIZE; i += 4) {
+        data = avio_rb32(pb) ^ (key = ((key << 3) | (key >> 29)) + key);
+        bytestream_put_be32(&pbc, data);
+    }
+
+    codec->codec_id    = AV_CODEC_ID_ADPCM_THP;
+    codec->codec_type  = AVMEDIA_TYPE_AUDIO;
+
+    bytestream2_init(&gbc, header, HEADER_SIZE);
+    bytestream2_seek(&gbc, 0x3c, SEEK_SET);
+    codec->sample_rate = bytestream2_get_be32u(&gbc);
+    if (codec->sample_rate <= 0 || codec->sample_rate > 96000) {
+        av_log(s, AV_LOG_ERROR, "Invalid sample rate: %d\n", codec->sample_rate);
+        return AVERROR_INVALIDDATA;
+    }
+
+    st->duration = bytestream2_get_be32u(&gbc) * 14;
+    redspark->samples_count = 0;
+    bytestream2_skipu(&gbc, 10);
+    codec->channels = bytestream2_get_byteu(&gbc);
+    if (!codec->channels)
+        return AVERROR_INVALIDDATA;
+
+    coef_off = 0x54 + codec->channels * 8;
+    if (bytestream2_get_byteu(&gbc)) // Loop flag
+        coef_off += 16;
+
+    codec->extradata_size = 32 * codec->channels;
+    codec->extradata = av_malloc(codec->extradata_size);
+    if (!codec->extradata)
+        return AVERROR(ENOMEM);
+
+    /* Get the ADPCM table */
+    bytestream2_seek(&gbc, coef_off, SEEK_SET);
+    for (i = 0; i < codec->channels; i++) {
+        if (bytestream2_get_bufferu(&gbc, codec->extradata + i * 32, 32) != 32)
+            return AVERROR_INVALIDDATA;
+        bytestream2_skipu(&gbc, 14);
+    }
+
+    avpriv_set_pts_info(st, 64, 1, codec->sample_rate);
+
+    return 0;
+}
+
+static int redspark_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    AVCodecContext *codec = s->streams[0]->codec;
+    RedSparkContext *redspark = s->priv_data;
+    uint32_t size = 8 * codec->channels;
+    int ret;
+
+    if (url_feof(s->pb) || redspark->samples_count == s->streams[0]->duration)
+        return AVERROR_EOF;
+
+    ret = av_get_packet(s->pb, pkt, size);
+    if (ret != size) {
+        av_free_packet(pkt);
+        return AVERROR(EIO);
+    }
+
+    pkt->duration = 14;
+    redspark->samples_count += pkt->duration;
+    pkt->stream_index = 0;
+
+    return ret;
+}
+
+AVInputFormat ff_redspark_demuxer = {
+    .name           =   "redspark",
+    .long_name      =   NULL_IF_CONFIG_SMALL("RedSpark"),
+    .priv_data_size =   sizeof(RedSparkContext),
+    .read_probe     =   redspark_probe,
+    .read_header    =   redspark_read_header,
+    .read_packet    =   redspark_read_packet,
+    .extensions     =   "rsd",
+};