You've already forked FFmpeg
mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2025-11-23 21:54:53 +02:00
0971fcf0a0
The aim of this is twofold: a) Clang warns when setting a deprecated
field in a definition and because several of the widely set
AVCodec fields are deprecated, one gets several hundred warnings
from Clang for an ordinary build. Yet fortunately Clang (unlike GCC)
allows to disable deprecation warnings inside a definition, so
that one can create simple macros to set these fields that also suppress
deprecation warnings for Clang. This has already been done in
fdff1b9cbf for AVCodec.channel_layouts.
b) Using macros will allow to easily migrate these fields to internal ones.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
122 lines
3.4 KiB
C
122 lines
3.4 KiB
C
/*
|
|
* DFPWM encoder
|
|
* Copyright (c) 2022 Jack Bruienne
|
|
* Copyright (c) 2012, 2016 Ben "GreaseMonkey" Russell
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* DFPWM1a encoder
|
|
*/
|
|
|
|
#include "libavutil/internal.h"
|
|
#include "avcodec.h"
|
|
#include "codec_id.h"
|
|
#include "codec_internal.h"
|
|
#include "encode.h"
|
|
|
|
typedef struct {
|
|
int fq, q, s, lt;
|
|
} DFPWMState;
|
|
|
|
// DFPWM codec from https://github.com/ChenThread/dfpwm/blob/master/1a/
|
|
// Licensed in the public domain
|
|
|
|
// note, len denotes how many compressed bytes there are (uncompressed bytes / 8).
|
|
static void au_compress(DFPWMState *state, int len, uint8_t *outbuf, const uint8_t *inbuf)
|
|
{
|
|
unsigned d = 0;
|
|
for (int i = 0; i < len; i++) {
|
|
for (int j = 0; j < 8; j++) {
|
|
int nq, st, ns;
|
|
// get sample
|
|
int v = *(inbuf++) - 128;
|
|
// set bit / target
|
|
int t = (v > state->q || (v == state->q && v == 127) ? 127 : -128);
|
|
d >>= 1;
|
|
if(t > 0)
|
|
d |= 0x80;
|
|
|
|
// adjust charge
|
|
nq = state->q + ((state->s * (t-state->q) + 512)>>10);
|
|
if(nq == state->q && nq != t)
|
|
nq += (t == 127 ? 1 : -1);
|
|
state->q = nq;
|
|
|
|
// adjust strength
|
|
st = (t != state->lt ? 0 : 1023);
|
|
ns = state->s;
|
|
if(ns != st)
|
|
ns += (st != 0 ? 1 : -1);
|
|
if(ns < 8) ns = 8;
|
|
state->s = ns;
|
|
|
|
state->lt = t;
|
|
}
|
|
|
|
// output bits
|
|
*(outbuf++) = d;
|
|
}
|
|
}
|
|
|
|
static av_cold int dfpwm_enc_init(struct AVCodecContext *ctx)
|
|
{
|
|
DFPWMState *state = ctx->priv_data;
|
|
|
|
state->fq = 0;
|
|
state->q = 0;
|
|
state->s = 0;
|
|
state->lt = -128;
|
|
|
|
ctx->bits_per_coded_sample = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dfpwm_enc_frame(struct AVCodecContext *ctx, struct AVPacket *packet,
|
|
const struct AVFrame *frame, int *got_packet)
|
|
{
|
|
DFPWMState *state = ctx->priv_data;
|
|
int size = frame->nb_samples * frame->ch_layout.nb_channels / 8 + (frame->nb_samples % 8 > 0 ? 1 : 0);
|
|
int ret = ff_get_encode_buffer(ctx, packet, size, 0);
|
|
|
|
if (ret) {
|
|
*got_packet = 0;
|
|
return ret;
|
|
}
|
|
|
|
au_compress(state, size, packet->data, frame->data[0]);
|
|
|
|
*got_packet = 1;
|
|
return 0;
|
|
}
|
|
|
|
const FFCodec ff_dfpwm_encoder = {
|
|
.p.name = "dfpwm",
|
|
CODEC_LONG_NAME("DFPWM1a audio"),
|
|
.p.type = AVMEDIA_TYPE_AUDIO,
|
|
.p.id = AV_CODEC_ID_DFPWM,
|
|
.priv_data_size = sizeof(DFPWMState),
|
|
.init = dfpwm_enc_init,
|
|
FF_CODEC_ENCODE_CB(dfpwm_enc_frame),
|
|
CODEC_SAMPLEFMTS(AV_SAMPLE_FMT_U8),
|
|
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_VARIABLE_FRAME_SIZE |
|
|
AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
|
|
};
|