[FFmpeg-devel] [PATCH 2/2] tta encoder
Paul B Mahol
onemda at gmail.com
Mon May 27 22:46:27 CEST 2013
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/general.texi | 2 +-
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 2 +-
libavcodec/ttaenc.c | 209 +++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 212 insertions(+), 2 deletions(-)
create mode 100644 libavcodec/ttaenc.c
diff --git a/doc/general.texi b/doc/general.texi
index 41dc214..1d6e236 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -899,7 +899,7 @@ following image formats are supported:
@item Speex @tab E @tab E
@tab supported through external library libspeex
@item TAK (Tom's lossless Audio Kompressor) @tab @tab X
- at item True Audio (TTA) @tab @tab X
+ at item True Audio (TTA) @tab X @tab X
@item TrueHD @tab @tab X
@tab Used in HD-DVD and Blu-Ray discs.
@item TwinVQ (VQF flavor) @tab @tab X
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 624b8fb..c9bd201 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -430,6 +430,7 @@ OBJS-$(CONFIG_TRUESPEECH_DECODER) += truespeech.o
OBJS-$(CONFIG_TSCC_DECODER) += tscc.o msrledec.o
OBJS-$(CONFIG_TSCC2_DECODER) += tscc2.o
OBJS-$(CONFIG_TTA_DECODER) += tta.o ttadata.o
+OBJS-$(CONFIG_TTA_ENCODER) += ttaenc.o ttadata.o
OBJS-$(CONFIG_TWINVQ_DECODER) += twinvq.o
OBJS-$(CONFIG_TXD_DECODER) += txd.o s3tc.o
OBJS-$(CONFIG_ULTI_DECODER) += ulti.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index a6b3e72..60e921e 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -366,7 +366,7 @@ void avcodec_register_all(void)
REGISTER_DECODER(TAK, tak);
REGISTER_DECODER(TRUEHD, truehd);
REGISTER_DECODER(TRUESPEECH, truespeech);
- REGISTER_DECODER(TTA, tta);
+ REGISTER_ENCDEC (TTA, tta);
REGISTER_DECODER(TWINVQ, twinvq);
REGISTER_DECODER(VMDAUDIO, vmdaudio);
REGISTER_ENCDEC (VORBIS, vorbis);
diff --git a/libavcodec/ttaenc.c b/libavcodec/ttaenc.c
new file mode 100644
index 0000000..51c1f0c
--- /dev/null
+++ b/libavcodec/ttaenc.c
@@ -0,0 +1,209 @@
+/*
+ * TTA (The Lossless True Audio) encoder
+ *
+ * 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
+ */
+
+#define BITSTREAM_WRITER_LE
+#include "ttadata.h"
+#include "avcodec.h"
+#include "put_bits.h"
+#include "internal.h"
+#include "libavutil/crc.h"
+
+typedef struct TTAEncContext {
+ const AVCRC *crc_table;
+ int bps;
+ TTAChannel *ch_ctx;
+} TTAEncContext;
+
+static av_cold int tta_encode_init(AVCodecContext *avctx)
+{
+ TTAEncContext *s = avctx->priv_data;
+
+ s->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
+
+ switch (avctx->sample_fmt) {
+ case AV_SAMPLE_FMT_U8:
+ avctx->bits_per_raw_sample = 8;
+ break;
+ case AV_SAMPLE_FMT_S16:
+ avctx->bits_per_raw_sample = 16;
+ break;
+ case AV_SAMPLE_FMT_S32:
+ if (avctx->bits_per_raw_sample > 24)
+ av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
+ avctx->bits_per_raw_sample = 24;
+ }
+
+ s->bps = avctx->bits_per_raw_sample >> 3;
+ avctx->frame_size = 256 * avctx->sample_rate / 245;
+
+ s->ch_ctx = av_malloc(avctx->channels * sizeof(*s->ch_ctx));
+ if (!s->ch_ctx)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static inline void ttafilter_process(TTAFilter *c, int32_t *in)
+{
+ register int32_t *dl = c->dl, *qm = c->qm, *dx = c->dx, sum = c->round;
+
+ if (c->error < 0) {
+ qm[0] -= dx[0]; qm[1] -= dx[1]; qm[2] -= dx[2]; qm[3] -= dx[3];
+ qm[4] -= dx[4]; qm[5] -= dx[5]; qm[6] -= dx[6]; qm[7] -= dx[7];
+ } else if (c->error > 0) {
+ qm[0] += dx[0]; qm[1] += dx[1]; qm[2] += dx[2]; qm[3] += dx[3];
+ qm[4] += dx[4]; qm[5] += dx[5]; qm[6] += dx[6]; qm[7] += dx[7];
+ }
+
+ sum += dl[0] * qm[0] + dl[1] * qm[1] + dl[2] * qm[2] + dl[3] * qm[3] +
+ dl[4] * qm[4] + dl[5] * qm[5] + dl[6] * qm[6] + dl[7] * qm[7];
+
+ dx[0] = dx[1]; dx[1] = dx[2]; dx[2] = dx[3]; dx[3] = dx[4];
+ dl[0] = dl[1]; dl[1] = dl[2]; dl[2] = dl[3]; dl[3] = dl[4];
+
+ dx[4] = ((dl[4] >> 30) | 1);
+ dx[5] = ((dl[5] >> 30) | 2) & ~1;
+ dx[6] = ((dl[6] >> 30) | 2) & ~1;
+ dx[7] = ((dl[7] >> 30) | 4) & ~3;
+
+ dl[4] = -dl[5]; dl[5] = -dl[6];
+ dl[6] = *in - dl[7]; dl[7] = *in;
+ dl[5] += dl[6]; dl[4] += dl[5];
+
+ *in -= (sum >> c->shift);
+ c->error = *in;
+}
+
+static int tta_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
+ const AVFrame *frame, int *got_packet_ptr)
+{
+ TTAEncContext *s = avctx->priv_data;
+ PutBitContext pb;
+ int16_t *samples = (int16_t *)frame->data[0];
+ int32_t value, next, temp;
+ int ret, i, out_bytes, cur_chan = 0, res = 0;
+
+ if ((ret = ff_alloc_packet2(avctx, avpkt, frame->nb_samples * 5)) < 0)
+ return ret;
+ init_put_bits(&pb, avpkt->data, avpkt->size);
+
+ // init per channel states
+ for (i = 0; i < avctx->channels; i++) {
+ s->ch_ctx[i].predictor = 0;
+ ff_tta_filter_init(&s->ch_ctx[i].filter, ff_tta_filter_configs[s->bps-1]);
+ ff_tta_rice_init(&s->ch_ctx[i].rice, 10, 10);
+ }
+
+ next = *samples++;
+ for (i = 0; i < frame->nb_samples * avctx->channels; i++) {
+ TTAChannel *c = &s->ch_ctx[cur_chan];
+ TTARice *rice = &c->rice;
+ uint32_t k, unary, outval;
+
+ value = next;
+ next = *samples++;
+
+ if (avctx->channels > 1) {
+ if (cur_chan < avctx->channels - 1)
+ value = res = next - value;
+ else
+ value -= res / 2;
+ }
+
+ temp = value;
+#define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k)
+ value -= PRED(c->predictor, 5);
+ c->predictor = temp;
+
+ ttafilter_process(&c->filter, &value);
+ outval = (value > 0) ? (value << 1) - 1: -value << 1;
+
+ k = rice->k0;
+
+ rice->sum0 += outval - (rice->sum0 >> 4);
+ if (rice->k0 > 0 && rice->sum0 < ff_tta_shift_16[rice->k0])
+ rice->k0--;
+ else if (rice->sum0 > ff_tta_shift_16[rice->k0 + 1])
+ rice->k0++;
+
+ if (outval >= ff_tta_shift_1[k]) {
+ outval -= ff_tta_shift_1[k];
+ k = rice->k1;
+
+ rice->sum1 += outval - (rice->sum1 >> 4);
+ if (rice->k1 > 0 && rice->sum1 < ff_tta_shift_16[rice->k1])
+ rice->k1--;
+ else if (rice->sum1 > ff_tta_shift_16[rice->k1 + 1])
+ rice->k1++;
+
+ unary = 1 + (outval >> k);
+ } else {
+ unary = 0;
+ }
+
+ if (unary)
+ put_bits(&pb, unary, (1 << unary) - 1);
+ put_bits(&pb, 1, 0);
+
+ if (k)
+ put_bits(&pb, k, outval & (ff_tta_shift_1[k] - 1));
+
+ if (cur_chan < avctx->channels - 1)
+ cur_chan++;
+ else
+ cur_chan = 0;
+ }
+
+ out_bytes = (put_bits_count(&pb) + 7) >> 3;
+ flush_put_bits(&pb);
+ put_bits32(&pb, av_crc(s->crc_table, 0xFFFFFFFFU, avpkt->data, out_bytes) ^ 0xFFFFFFFFU);
+ flush_put_bits(&pb);
+
+ avpkt->pts = frame->pts;
+ avpkt->size = out_bytes + 4;
+ avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
+ *got_packet_ptr = 1;
+ return 0;
+}
+
+static av_cold int tta_encode_close(AVCodecContext *avctx)
+{
+ TTAEncContext *s = avctx->priv_data;
+
+ av_freep(&s->ch_ctx);
+
+ return 0;
+}
+
+AVCodec ff_tta_encoder = {
+ .name = "tta",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_TTA,
+ .priv_data_size = sizeof(TTAEncContext),
+ .init = tta_encode_init,
+ .close = tta_encode_close,
+ .encode2 = tta_encode_frame,
+ .capabilities = CODEC_CAP_SMALL_LAST_FRAME | CODEC_CAP_LOSSLESS,
+ .sample_fmts = (const enum AVSampleFormat[]){ /* AV_SAMPLE_FMT_U8, */
+ AV_SAMPLE_FMT_S16,
+ /* AV_SAMPLE_FMT_S32, */
+ AV_SAMPLE_FMT_NONE },
+ .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
+};
--
1.7.11.2
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