On 16/04/14 16:52, Kostya Shishkov wrote:
> On Wed, Apr 16, 2014 at 04:13:19PM +0200, Luca Barbato wrote:
>> From: Peter Ross <[email protected]>
>>
>> Signed-off-by: Peter Ross <[email protected]>
>> Signed-off-by: Michael Niedermayer <[email protected]>
>> Signed-off-by: Jean-Baptiste Kempf <[email protected]>
>> Signed-off-by: Luca Barbato <[email protected]>
>> ---
>>
>> The tests are missing, Vittorio willing to bake some?
>>
>>  Changelog                 |   1 +
>>  doc/general.texi          |   4 +
>>  libavcodec/Makefile       |   8 +-
>>  libavcodec/allcodecs.c    |   4 +
>>  libavcodec/avcodec.h      |   4 +
>>  libavcodec/codec_desc.c   |  28 +++++++
>>  libavcodec/dsd_tablegen.c |  38 ++++++++++
>>  libavcodec/dsd_tablegen.h |  95 ++++++++++++++++++++++++
>>  libavcodec/dsddec.c       | 185 
>> ++++++++++++++++++++++++++++++++++++++++++++++
>>  libavcodec/utils.c        |   4 +
>>  10 files changed, 370 insertions(+), 1 deletion(-)
>>  create mode 100644 libavcodec/dsd_tablegen.c
>>  create mode 100644 libavcodec/dsd_tablegen.h
>>  create mode 100644 libavcodec/dsddec.c
>>
>> diff --git a/Changelog b/Changelog
>> index 55216e8..d895b94 100644
>> --- a/Changelog
>> +++ b/Changelog
>> @@ -19,6 +19,7 @@ version <next>:
>>  - LucasArts SMUSH demuxer
>>  - MP2 encoding via TwoLAME
>>  - asettb filter
>> +- Direct Stream Digital (DSD) decoder
>>
>>
>>  version 10:
>> diff --git a/doc/general.texi b/doc/general.texi
>> index 2612eb1..4b16075 100644
>> --- a/doc/general.texi
>> +++ b/doc/general.texi
>> @@ -822,6 +822,10 @@ following image formats are supported:
>>  @item DPCM Sol               @tab     @tab  X
>>  @item DPCM Xan               @tab     @tab  X
>>      @tab Used in Origin's Wing Commander IV AVI files.
>> +@item DSD (Direct Stream Digitial), least significant bit first  @tab  @tab 
>>  X
>> +@item DSD (Direct Stream Digitial), most significant bit first   @tab  @tab 
>>  X
>> +@item DSD (Direct Stream Digitial), least significant bit first, planar  
>> @tab  @tab  X
>> +@item DSD (Direct Stream Digitial), most significant bit first, planar   
>> @tab  @tab  X
> 
> one item should be enough
> 
>>  @item DSP Group TrueSpeech   @tab     @tab  X
>>  @item DV audio               @tab     @tab  X
>>  @item Enhanced AC-3          @tab  X  @tab  X
> [...]
>> diff --git a/libavcodec/dsd_tablegen.h b/libavcodec/dsd_tablegen.h
>> new file mode 100644
>> index 0000000..0bebaea
>> --- /dev/null
>> +++ b/libavcodec/dsd_tablegen.h
>> @@ -0,0 +1,95 @@
>> +/*
>> + * Header file for hardcoded DSD tables
>> + * based on BSD licensed dsd2pcm by Sebastian Gesemann
>> + * Copyright (c) 2009, 2011 Sebastian Gesemann. All rights reserved.
>> + *
>> + * This file is part of Libav.
>> + *
>> + * Libav 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.
>> + *
>> + * Libav 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 Libav; if not, write to the Free Software
>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 
>> USA
>> + */
>> +
>> +#ifndef AVCODEC_DSD_TABLEGEN_H
>> +#define AVCODEC_DSD_TABLEGEN_H
>> +
>> +#include <stdint.h>
>> +#include "libavutil/attributes.h"
>> +
>> +#define HTAPS   48                /** number of FIR constants */
>> +#define CTABLES ((HTAPS + 7) / 8) /** number of "8 MACs" lookup tables */
>> +
>> +#if CONFIG_HARDCODED_TABLES
>> +#define dsd_ctables_tableinit()
>> +#include "libavcodec/dsd_tables.h"
>> +#else
>> +#include "libavutil/common.h"
>> +
>> +/*
>> + * Properties of this 96-tap lowpass filter when applied on a signal
>> + * with sampling rate of 44100*64 Hz:
>> + *
>> + * () has a delay of 17 microseconds.
> 
> ()?
> 
>> + *
>> + * () flat response up to 48 kHz
>> + *
>> + * () if you downsample afterwards by a factor of 8, the
>> + *    spectrum below 70 kHz is practically alias-free.
>> + *
>> + * () stopband rejection is about 160 dB
>> + *
>> + * The coefficient tables ("ctables") take only 6 Kibi Bytes and
> 
> barf
> 
>> + * should fit into a modern processor's fast cache.
>> + */
>> +
>> +/**
>> + * The 2nd half (48 coeffs) of a 96-tap symmetric lowpass filter
>> + */
>> +static const double htaps[HTAPS] = {
>> +     0.09950731974056658,    0.09562845727714668,    0.08819647126516944,
>> +     0.07782552527068175,    0.06534876523171299,    0.05172629311427257,
>> +     0.0379429484910187,     0.02490921351762261,    0.0133774746265897,
>> +     0.003883043418804416,  -0.003284703416210726,  -0.008080250212687497,
>> +    -0.01067241812471033,   -0.01139427235000863,   -0.0106813877974587,
>> +    -0.009007905078766049,  -0.006828859761015335,  -0.004535184322001496,
>> +    -0.002425035959059578,  -0.0006922187080790708,  0.0005700762133516592,
>> +     0.001353838005269448,   0.001713709169690937,   0.001742046839472948,
>> +     0.001545601648013235,   0.001226696225277855,   0.0008704322683580222,
>> +     0.0005381636200535649,  0.000266446345425276,   7.002968738383528e-05,
>> +    -5.279407053811266e-05, -0.0001140625650874684, -0.0001304796361231895,
>> +    -0.0001189970287491285, -9.396247155265073e-05, -6.577634378272832e-05,
>> +    -4.07492895872535e-05,  -2.17407957554587e-05,  -9.163058931391722e-06,
>> +    -2.017460145032201e-06,  1.249721855219005e-06,  2.166655190537392e-06,
>> +     1.930520892991082e-06,  1.319400334374195e-06,  7.410039764949091e-07,
>> +     3.423230509967409e-07,  1.244182214744588e-07,  3.130441005359396e-08
>> +};
>> +
>> +static float ctables[CTABLES][256];
>> +
>> +static av_cold void dsd_ctables_tableinit(void)
>> +{
>> +    int t, e, m, k;
>> +    double acc;
>> +    for (t = 0; t < CTABLES; ++t) {
>> +        k = FFMIN(HTAPS - t * 8, 8);
> 
> unless one decides to switch to non-multiple-of-8 tap filter k=8 in all cases
> (otherwise one can pad filter anyway and see above)
> 
>> +        for (e = 0; e < 256; ++e) {
>> +            acc = 0.0;
>> +            for (m = 0; m < k; ++m)
>> +                acc += (((e >> (7 - m)) & 1) * 2 - 1) * htaps[t * 8 + m];
>> +            ctables[CTABLES - 1 - t][e] = (float)acc;
>> +        }
>> +    }
>> +}
>> +#endif /* CONFIG_HARDCODED_TABLES */
>> +
>> +#endif /* AVCODEC_DSD_TABLEGEN_H */
>> diff --git a/libavcodec/dsddec.c b/libavcodec/dsddec.c
>> new file mode 100644
>> index 0000000..6876f16
>> --- /dev/null
>> +++ b/libavcodec/dsddec.c
>> @@ -0,0 +1,185 @@
>> +/*
>> + * Direct Stream Digital (DSD) decoder
>> + * based on BSD licensed dsd2pcm by Sebastian Gesemann
>> + * Copyright (c) 2009, 2011 Sebastian Gesemann. All rights reserved.
>> + * Copyright (c) 2014 Peter Ross
>> + *
>> + * This file is part of Libav.
>> + *
>> + * Libav 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.
>> + *
>> + * Libav 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 Libav; if not, write to the Free Software
>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 
>> USA
>> + */
>> +
>> +/**
>> + * @file
>> + * Direct Stream Digital (DSD) decoder
>> + */
>> +
>> +#include "libavcodec/internal.h"
>> +#include "libavcodec/mathops.h"
>> +#include "avcodec.h"
>> +#include "dsd_tablegen.h"
>> +
>> +#define FIFOSIZE 16              /** must be a power of two */
>> +#define FIFOMASK (FIFOSIZE - 1)  /** bit mask for FIFO offsets */
>> +
>> +#if FIFOSIZE * 8 < HTAPS * 2
>> +#error "FIFOSIZE too small"
>> +#endif
>> +
>> +/*
>> + * Per-channel buffer
>> + */
>> +typedef struct {
>> +    unsigned char buf[FIFOSIZE];
> 
> uint8_t?
> 
>> +    unsigned pos;
>> +} DSDContext;
>> +
>> +static void dsd2pcm_translate(DSDContext* s, size_t samples, int lsbf,
>> +                              const uint8_t *src, ptrdiff_t src_stride,
>> +                              float *dst, ptrdiff_t dst_stride)
>> +{
>> +    unsigned int pos, i;
>> +    uint8_t *p;
>> +    double sum;
>> +
>> +    pos = s->pos;
>> +
>> +    while (samples-- > 0) {
> 
> while (samples--)
> 
> it's more honest here
> 
>> +        s->buf[pos] = lsbf ? ff_reverse[*src] : *src;
>> +        src += src_stride;
>> +
>> +        p = s->buf + ((pos - CTABLES) & FIFOMASK);
>> +        *p = ff_reverse[*p];
>> +
>> +        sum = 0.0;
>> +        for (i = 0; i < CTABLES; i++) {
>> +            const uint8_t a = s->buf[(pos                     - i) & 
>> FIFOMASK];
>> +            const uint8_t b = s->buf[(pos - (CTABLES * 2 - 1) + i) & 
>> FIFOMASK];
>> +            sum += ctables[i][a] + ctables[i][b];
>> +        }
>> +
>> +        *dst = (float)sum;
>> +        dst += dst_stride;
>> +
>> +        pos = (pos + 1) & FIFOMASK;
>> +    }
>> +
>> +    s->pos = pos;
>> +}
>> +
>> +static av_cold void dsd_init_static_data(AVCodec *unused)
>> +{
>> +    dsd_ctables_tableinit();
>> +}
>> +
>> +static av_cold int dsd_decode_init(AVCodecContext *avctx)
>> +{
>> +    DSDContext * s;
>> +    int i;
>> +
>> +    s = av_malloc(sizeof(DSDContext) * avctx->channels);
>> +    if (!s)
>> +        return AVERROR(ENOMEM);
>> +
>> +    for (i = 0; i < avctx->channels; i++) {
>> +        s[i].pos = 0;
>> +        memset(s[i].buf, 0x69, sizeof(s[i].buf));
>> +
>> +        /* 0x69 = 01101001
>> +         * This pattern "on repeat" makes a low energy 352.8 kHz tone
>> +         * and a high energy 1.0584 MHz tone which should be filtered
>> +         * out completely by any playback system --> silence
>> +         */
>> +    }
>> +
>> +    avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
>> +    avctx->priv_data  = s;
>> +    return 0;
>> +}
>> +
>> +static av_always_inline
>> +int dsd_decode_frame_internal(AVCodecContext *avctx, void *data,
>> +                              int *got_frame_ptr, AVPacket *avpkt,
>> +                              int lsbf, int planar)
>> +{
>> +    DSDContext * s = avctx->priv_data;
>> +    AVFrame *frame = data;
>> +    int ret, i;
>> +    int src_next;
>> +    int src_stride;
>> +
>> +    frame->nb_samples = avpkt->size / avctx->channels;
>> +
>> +    if (planar) {
>> +        src_next   = frame->nb_samples;
>> +        src_stride = 1;
>> +    } else {
>> +        src_next   = 1;
>> +        src_stride = avctx->channels;
>> +    }
>> +
>> +    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
>> +        return ret;
>> +
>> +    for (i = 0; i < avctx->channels; i++) {
>> +        float *dst = ((float **)frame->extended_data)[i];
>> +        dsd2pcm_translate(&s[i], frame->nb_samples, lsbf,
>> +                          avpkt->data + i * src_next, src_stride,
>> +                          dst, 1);
>> +    }
>> +
>> +    *got_frame_ptr = 1;
>> +    return frame->nb_samples * avctx->channels;
>> +}
>> +
>> +static int dsd_lsbf_decode_frame(AVCodecContext *avctx, void *data,
>> +                                 int *got_frame, AVPacket *avpkt)
>> +{
>> +    return dsd_decode_frame_internal(avctx, data, got_frame, avpkt, 1, 0);
>> +}
> 
> empty line missing
> 
>> +static int dsd_msbf_decode_frame(AVCodecContext *avctx, void *data,
>> +                                 int *got_frame, AVPacket *avpkt)
>> +{
>> +    return dsd_decode_frame_internal(avctx, data, got_frame, avpkt, 0, 0);
>> +}
>> +
>> +static int dsd_lsbf_planar_decode_frame(AVCodecContext *avctx, void *data,
>> +                                        int *got_frame, AVPacket *avpkt)
>> +{
>> +    return dsd_decode_frame_internal(avctx, data, got_frame, avpkt, 1, 1);
>> +}
>> +static int dsd_msbf_planar_decode_frame(AVCodecContext *avctx, void *data,
>> +                                        int *got_frame, AVPacket *avpkt)
>> +{
>> +    return dsd_decode_frame_internal(avctx, data, got_frame, avpkt, 0, 1);
>> +}
>> +
>> +#define DSD_DECODER(id_, name_, long_name_) \
>> +AVCodec ff_##name_##_decoder = { \
>> +    .name             = #name_, \
>> +    .long_name        = NULL_IF_CONFIG_SMALL(long_name_), \
>> +    .type             = AVMEDIA_TYPE_AUDIO, \
>> +    .id               = AV_CODEC_ID_##id_, \
>> +    .init             = dsd_decode_init, \
>> +    .decode           = name_ ## _decode_frame, \
>> +    .init_static_data = dsd_init_static_data, \
>> +    .sample_fmts      = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP, \
>> +                                                       AV_SAMPLE_FMT_NONE 
>> }, \
>> +};
>> +
>> +DSD_DECODER(DSD_LSBF, dsd_lsbf, "DSD (Direct Stream Digital), least 
>> significant bit first")
>> +DSD_DECODER(DSD_MSBF, dsd_msbf, "DSD (Direct Stream Digital), most 
>> significant bit first")
>> +DSD_DECODER(DSD_MSBF_PLANAR, dsd_msbf_planar, "DSD (Direct Stream Digital), 
>> most significant bit first, planar")
>> +DSD_DECODER(DSD_LSBF_PLANAR, dsd_lsbf_planar, "DSD (Direct Stream Digital), 
>> least significant bit first, planar")
> 
> I wonder if it makes sense to contract it to "LSB/MSB first"
> 
>> diff --git a/libavcodec/utils.c b/libavcodec/utils.c
>> index d9832e2..38a138b 100644
>> --- a/libavcodec/utils.c
>> +++ b/libavcodec/utils.c
>> @@ -1929,6 +1929,10 @@ int av_get_exact_bits_per_sample(enum AVCodecID 
>> codec_id)
>>      case AV_CODEC_ID_ADPCM_G722:
>>      case AV_CODEC_ID_ADPCM_YAMAHA:
>>          return 4;
>> +    case AV_CODEC_ID_DSD_LSBF:
>> +    case AV_CODEC_ID_DSD_MSBF:
>> +    case AV_CODEC_ID_DSD_LSBF_PLANAR:
>> +    case AV_CODEC_ID_DSD_MSBF_PLANAR:
>>      case AV_CODEC_ID_PCM_ALAW:
>>      case AV_CODEC_ID_PCM_MULAW:
>>      case AV_CODEC_ID_PCM_S8:
>> --
> 
> in general LGTM

Everything mentioned fixed, shall I push it or wait for jb to source the
demuxer bits?

lu

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