[FFmpeg-devel] [PATCH 2/3] sbc: add parser for SBC
Rostislav Pehlivanov
atomnuker at gmail.com
Mon Nov 6 01:43:37 EET 2017
On 5 November 2017 at 23:35, Aurelien Jacobs <aurel at gnuage.org> wrote:
> ---
> libavcodec/Makefile | 2 +
> libavcodec/allcodecs.c | 2 +
> libavcodec/sbc_parser.c | 135 ++++++++++++++++++++++++++++++
> ++++++++++++++++++
> 3 files changed, 139 insertions(+)
> create mode 100644 libavcodec/sbc_parser.c
>
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 17648a1c3d..a15573748d 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -994,11 +994,13 @@ OBJS-$(CONFIG_PNG_PARSER) +=
> png_parser.o
> OBJS-$(CONFIG_MPEGAUDIO_PARSER) += mpegaudio_parser.o
> OBJS-$(CONFIG_MPEGVIDEO_PARSER) += mpegvideo_parser.o \
> mpeg12.o mpeg12data.o
> +OBJS-$(CONFIG_MSBC_PARSER) += sbc_parser.o
> OBJS-$(CONFIG_OPUS_PARSER) += opus_parser.o opus.o
> vorbis_data.o
> OBJS-$(CONFIG_PNG_PARSER) += png_parser.o
> OBJS-$(CONFIG_PNM_PARSER) += pnm_parser.o pnm.o
> OBJS-$(CONFIG_RV30_PARSER) += rv34_parser.o
> OBJS-$(CONFIG_RV40_PARSER) += rv34_parser.o
> +OBJS-$(CONFIG_SBC_PARSER) += sbc_parser.o
> OBJS-$(CONFIG_SIPR_PARSER) += sipr_parser.o
> OBJS-$(CONFIG_TAK_PARSER) += tak_parser.o tak.o
> OBJS-$(CONFIG_VC1_PARSER) += vc1_parser.o vc1.o vc1data.o \
> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
> index 95cf67ce20..02d241c4f3 100644
> --- a/libavcodec/allcodecs.c
> +++ b/libavcodec/allcodecs.c
> @@ -717,11 +717,13 @@ static void register_all(void)
> REGISTER_PARSER(MPEG4VIDEO, mpeg4video);
> REGISTER_PARSER(MPEGAUDIO, mpegaudio);
> REGISTER_PARSER(MPEGVIDEO, mpegvideo);
> + REGISTER_PARSER(MSBC, msbc);
> REGISTER_PARSER(OPUS, opus);
> REGISTER_PARSER(PNG, png);
> REGISTER_PARSER(PNM, pnm);
> REGISTER_PARSER(RV30, rv30);
> REGISTER_PARSER(RV40, rv40);
> + REGISTER_PARSER(SBC, sbc);
> REGISTER_PARSER(SIPR, sipr);
> REGISTER_PARSER(TAK, tak);
> REGISTER_PARSER(VC1, vc1);
> diff --git a/libavcodec/sbc_parser.c b/libavcodec/sbc_parser.c
> new file mode 100644
> index 0000000000..278ac6f84f
> --- /dev/null
> +++ b/libavcodec/sbc_parser.c
> @@ -0,0 +1,135 @@
> +/*
> + * SBC parser
> + *
> + * Copyright (C) 2017 Aurelien Jacobs <aurel at gnuage.org>
> + *
> + * 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 "sbc.h"
> +#include "parser.h"
> +
> +typedef struct SBCParseContext {
> + ParseContext pc;
> + uint8_t header[3];
> + int header_size;
> + int buffered_size;
> +} SBCParseContext;
> +
> +static int sbc_parse_header(AVCodecParserContext *s, AVCodecContext
> *avctx,
> + const uint8_t *data, size_t len)
> +{
> + static const int sample_rates[4] = { 16000, 32000, 44100, 48000 };
> + int sr, blocks, mode, subbands, bitpool, channels, joint;
> + int length;
> +
> + if (len < 3)
> + return -1;
> +
> + if (data[0] == MSBC_SYNCWORD && data[1] == 0 && data[2] == 0) {
> + avctx->channels = 1;
> + avctx->sample_fmt = AV_SAMPLE_FMT_S16;
> + avctx->sample_rate = 16000;
> + avctx->frame_size = 120;
> + s->duration = avctx->frame_size;
> + return 57;
> + }
> +
> + if (data[0] != SBC_SYNCWORD)
> + return -2;
> +
> + sr = (data[1] >> 6) & 0x03;
> + blocks = (((data[1] >> 4) & 0x03) + 1) << 2;
> + mode = (data[1] >> 2) & 0x03;
> + subbands = (((data[1] >> 0) & 0x01) + 1) << 2;
> + bitpool = data[2];
> +
> + channels = mode == SBC_MODE_MONO ? 1 : 2;
> + joint = mode == SBC_MODE_JOINT_STEREO;
> +
> + length = 4 + (subbands * channels) / 2;
> + if (channels == 1 || mode == SBC_MODE_DUAL_CHANNEL)
> + length += ((channels * blocks * bitpool) + 7) / 8;
> + else
> + length += (((joint ? subbands : 0) + blocks * bitpool) + 7) / 8;
> +
> + avctx->channels = channels;
> + avctx->sample_fmt = AV_SAMPLE_FMT_S16;
> + avctx->sample_rate = sample_rates[sr];
> + avctx->frame_size = subbands * blocks;
> + s->duration = avctx->frame_size;
> + return length;
> +}
> +
> +static int sbc_parse(AVCodecParserContext *s, AVCodecContext *avctx,
> + const uint8_t **poutbuf, int *poutbuf_size,
> + const uint8_t *buf, int buf_size)
> +{
> + SBCParseContext *pc = s->priv_data;
> + int next;
> +
> + if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
> + next = buf_size;
> + } else {
> + if (pc->header_size) {
> + memcpy(pc->header + pc->header_size, buf,
> + sizeof(pc->header) - pc->header_size);
> + next = sbc_parse_header(s, avctx, pc->header,
> sizeof(pc->header))
> + - pc->buffered_size;
> + pc->header_size = 0;
> + } else {
> + next = sbc_parse_header(s, avctx, buf, buf_size);
> + if (next >= buf_size)
> + next = -1;
> + }
> +
> + if (next < 0) {
> + pc->header_size = FFMIN(sizeof(pc->header), buf_size);
> + memcpy(pc->header, buf, pc->header_size);
> + pc->buffered_size = buf_size;
> + next = END_NOT_FOUND;
> + }
> +
> + if (ff_combine_frame(&pc->pc, next, &buf, &buf_size) < 0) {
> + *poutbuf = NULL;
> + *poutbuf_size = 0;
> + return buf_size;
> + }
> + }
> +
> + *poutbuf = buf;
> + *poutbuf_size = buf_size;
> + return next;
> +}
> +
> +#if CONFIG_SBC_PARSER
> +AVCodecParser ff_sbc_parser = {
> + .codec_ids = { AV_CODEC_ID_SBC },
> + .priv_data_size = sizeof(SBCParseContext),
> + .parser_parse = sbc_parse,
> + .parser_close = ff_parse_close,
> +};
> +#endif
> +
> +#if CONFIG_MSBC_PARSER
> +AVCodecParser ff_msbc_parser = {
> + .codec_ids = { AV_CODEC_ID_MSBC },
> + .priv_data_size = sizeof(SBCParseContext),
> + .parser_parse = sbc_parse,
> + .parser_close = ff_parse_close,
> +};
> +#endif
>
Remove the msbc parser and add its codec ID to ff_sbc_parser.codec_ids,
since there's no difference in parsing between the two.
Apart from that lgtm.
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