diff options
Diffstat (limited to 'libavcodec/ttaenc.c')
-rw-r--r-- | libavcodec/ttaenc.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/libavcodec/ttaenc.c b/libavcodec/ttaenc.c new file mode 100644 index 0000000..3cc54d7 --- /dev/null +++ b/libavcodec/ttaenc.c @@ -0,0 +1,217 @@ +/* + * 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 "ttaencdsp.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; + TTAEncDSPContext dsp; +} 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_array(avctx->channels, sizeof(*s->ch_ctx)); + if (!s->ch_ctx) + return AVERROR(ENOMEM); + + ff_ttaencdsp_init(&s->dsp); + + return 0; +} + +static int32_t get_sample(const AVFrame *frame, int sample, + enum AVSampleFormat format) +{ + int32_t ret; + + if (format == AV_SAMPLE_FMT_U8) { + ret = frame->data[0][sample] - 0x80; + } else if (format == AV_SAMPLE_FMT_S16) { + const int16_t *ptr = (const int16_t *)frame->data[0]; + ret = ptr[sample]; + } else { + const int32_t *ptr = (const int32_t *)frame->data[0]; + ret = ptr[sample] >> 8; + } + + return ret; +} + +static int tta_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, + const AVFrame *frame, int *got_packet_ptr) +{ + TTAEncContext *s = avctx->priv_data; + PutBitContext pb; + int ret, i, out_bytes, cur_chan, res, samples; + int64_t pkt_size = frame->nb_samples * 2LL * avctx->channels * s->bps; + +pkt_alloc: + cur_chan = 0, res = 0, samples = 0; + if ((ret = ff_alloc_packet2(avctx, avpkt, pkt_size, 0)) < 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); + } + + for (i = 0; i < frame->nb_samples * avctx->channels; i++) { + TTAChannel *c = &s->ch_ctx[cur_chan]; + TTAFilter *filter = &c->filter; + TTARice *rice = &c->rice; + uint32_t k, unary, outval; + int32_t value, temp; + + value = get_sample(frame, samples++, avctx->sample_fmt); + + if (avctx->channels > 1) { + if (cur_chan < avctx->channels - 1) + value = res = get_sample(frame, samples, avctx->sample_fmt) - value; + else + value -= res / 2; + } + + temp = value; +#define PRED(x, k) (int32_t)((((uint64_t)(x) << (k)) - (x)) >> (k)) + switch (s->bps) { + case 1: value -= PRED(c->predictor, 4); break; + case 2: + case 3: value -= PRED(c->predictor, 5); break; + } + c->predictor = temp; + + s->dsp.filter_process(filter->qm, filter->dx, filter->dl, &filter->error, &value, + filter->shift, filter->round); + 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); + if (unary + 100LL > put_bits_left(&pb)) { + if (pkt_size < INT_MAX/2) { + pkt_size *= 2; + av_packet_unref(avpkt); + goto pkt_alloc; + } else + return AVERROR(ENOMEM); + } + do { + if (unary > 31) { + put_bits(&pb, 31, 0x7FFFFFFF); + unary -= 31; + } else { + put_bits(&pb, unary, (1 << unary) - 1); + unary = 0; + } + } while (unary); + } + + 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; + } + + flush_put_bits(&pb); + out_bytes = put_bits_count(&pb) >> 3; + put_bits32(&pb, av_crc(s->crc_table, UINT32_MAX, avpkt->data, out_bytes) ^ UINT32_MAX); + 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", + .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"), + .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 = AV_CODEC_CAP_SMALL_LAST_FRAME | AV_CODEC_CAP_LOSSLESS, + .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_U8, + AV_SAMPLE_FMT_S16, + AV_SAMPLE_FMT_S32, + AV_SAMPLE_FMT_NONE }, +}; |