avformat: add a TTA Muxer

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 149 insertions, 0 deletions

diff --git a/libavformat/ttaenc.c b/libavformat/ttaenc.c
new file mode 100644
index 0000000000..fdce1e3dc1
--- /dev/null
+++ b/libavformat/ttaenc.c
@@ -0,0 +1,149 @@
+/*
+ * True Audio (TTA) muxer
+ * Copyright (c) 2016 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 "libavutil/crc.h"
+#include "libavutil/intreadwrite.h"
+
+#include "apetag.h"
+#include "avformat.h"
+#include "avio_internal.h"
+#include "internal.h"
+
+typedef struct TTAMuxContext {
+    AVIOContext *seek_table;
+    AVIOContext *data;
+    uint32_t nb_samples;
+    int frame_size;
+    int last_frame;
+} TTAMuxContext;
+
+static int tta_write_header(AVFormatContext *s)
+{
+    TTAMuxContext *tta = s->priv_data;
+    AVCodecParameters *par = s->streams[0]->codecpar;
+    int ret;
+
+    if (s->nb_streams != 1) {
+        av_log(s, AV_LOG_ERROR, "Only one stream is supported\n");
+        return AVERROR(EINVAL);
+    }
+    if (par->codec_id != AV_CODEC_ID_TTA) {
+        av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
+        return AVERROR(EINVAL);
+    }
+    if (par->extradata && par->extradata_size < 22) {
+        av_log(s, AV_LOG_ERROR, "Invalid TTA extradata\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    if ((ret = avio_open_dyn_buf(&tta->seek_table)) < 0)
+        return ret;
+    if ((ret = avio_open_dyn_buf(&tta->data)) < 0) {
+        ffio_free_dyn_buf(&tta->seek_table);
+        return ret;
+    }
+
+    /* Ignore most extradata information if present. It can be innacurate
+       if for example remuxing from Matroska */
+    ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
+    ffio_init_checksum(tta->seek_table, ff_crcEDB88320_update, UINT32_MAX);
+    avio_write(s->pb, "TTA1", 4);
+    avio_wl16(s->pb, par->extradata ? AV_RL16(par->extradata + 4) : 1);
+    avio_wl16(s->pb, par->channels);
+    avio_wl16(s->pb, par->bits_per_raw_sample);
+    avio_wl32(s->pb, par->sample_rate);
+    /* Prevent overflow */
+    if (par->sample_rate > 0x7FFFFFu) {
+        av_log(s, AV_LOG_ERROR, "Sample rate too large\n");
+        return AVERROR(EINVAL);
+    }
+    tta->frame_size = par->sample_rate * 256 / 245;
+    avpriv_set_pts_info(s->streams[0], 64, 1, par->sample_rate);
+
+    return 0;
+}
+
+static int tta_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    TTAMuxContext *tta = s->priv_data;
+
+    avio_write(tta->data, pkt->data, pkt->size);
+    avio_wl32(tta->seek_table, pkt->size);
+    tta->nb_samples += pkt->duration;
+
+    if (tta->frame_size != pkt->duration) {
+        if (tta->last_frame) {
+            /* Two frames with a different duration than the default frame
+               size means the TTA stream comes from a faulty container, and
+               there's no way the last frame duration will be correct. */
+            av_log(s, AV_LOG_ERROR, "Invalid frame durations\n");
+
+            return AVERROR_INVALIDDATA;
+        }
+        /* First frame with a different duration than the default frame size.
+           Assume it's the last frame in the stream and continue. */
+        tta->last_frame++;
+    }
+
+    return 0;
+}
+
+static int tta_write_trailer(AVFormatContext *s)
+{
+    TTAMuxContext *tta = s->priv_data;
+    uint8_t *ptr;
+    unsigned int crc;
+    int size;
+
+    avio_wl32(s->pb, tta->nb_samples);
+    crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
+    avio_wl32(s->pb, crc);
+
+    /* Write Seek table */
+    crc = ffio_get_checksum(tta->seek_table) ^ UINT32_MAX;
+    avio_wl32(tta->seek_table, crc);
+    size = avio_close_dyn_buf(tta->seek_table, &ptr);
+    avio_write(s->pb, ptr, size);
+    av_free(ptr);
+
+    /* Write audio data */
+    size = avio_close_dyn_buf(tta->data, &ptr);
+    avio_write(s->pb, ptr, size);
+    av_free(ptr);
+
+    ff_ape_write_tag(s);
+    avio_flush(s->pb);
+
+    return 0;
+}
+
+AVOutputFormat ff_tta_muxer = {
+    .name              = "tta",
+    .long_name         = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
+    .mime_type         = "audio/x-tta",
+    .extensions        = "tta",
+    .priv_data_size    = sizeof(TTAMuxContext),
+    .audio_codec       = AV_CODEC_ID_TTA,
+    .video_codec       = AV_CODEC_ID_NONE,
+    .write_header      = tta_write_header,
+    .write_packet      = tta_write_packet,
+    .write_trailer     = tta_write_trailer,
+};