[FFmpeg-devel] [PATCH] avformat: add NSP demuxer

[Carl Eugen Hoyos]

2017-12-01 17:26 GMT+01:00 Paul B Mahol <onemda at gmail.com>:
> Signed-off-by: Paul B Mahol <onemda at gmail.com>
> ---
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/nspdec.c     | 101 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 103 insertions(+)
>  create mode 100644 libavformat/nspdec.c
>
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 4bffdf2205..734b703862 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -331,6 +331,7 @@ OBJS-$(CONFIG_MXF_MUXER)                 += mxfenc.o mxf.o audiointerleave.o
>  OBJS-$(CONFIG_MXG_DEMUXER)               += mxg.o
>  OBJS-$(CONFIG_NC_DEMUXER)                += ncdec.o
>  OBJS-$(CONFIG_NISTSPHERE_DEMUXER)        += nistspheredec.o pcm.o
> +OBJS-$(CONFIG_NSP_DEMUXER)               += nspdec.o
>  OBJS-$(CONFIG_NSV_DEMUXER)               += nsvdec.o
>  OBJS-$(CONFIG_NULL_MUXER)                += nullenc.o
>  OBJS-$(CONFIG_NUT_DEMUXER)               += nutdec.o nut.o isom.o
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index 9213af9301..6a9b9883c9 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -224,6 +224,7 @@ static void register_all(void)
>      REGISTER_DEMUXER (MXG,              mxg);
>      REGISTER_DEMUXER (NC,               nc);
>      REGISTER_DEMUXER (NISTSPHERE,       nistsphere);
> +    REGISTER_DEMUXER (NSP,              nsp);
>      REGISTER_DEMUXER (NSV,              nsv);
>      REGISTER_MUXER   (NULL,             null);
>      REGISTER_MUXDEMUX(NUT,              nut);
> diff --git a/libavformat/nspdec.c b/libavformat/nspdec.c
> new file mode 100644
> index 0000000000..d2ff779732
> --- /dev/null
> +++ b/libavformat/nspdec.c
> @@ -0,0 +1,101 @@
> +/*
> + * NSP demuxer
> + * Copyright (c) 2017 Paul B Mahol
> + *
> + * 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 "libavutil/avstring.h"
> +#include "libavutil/intreadwrite.h"
> +#include "avformat.h"
> +#include "internal.h"
> +#include "pcm.h"
> +
> +static int nsp_probe(AVProbeData *p)
> +{
> +    if (AV_RB32(p->buf) == AV_RB32("FORM") &&
> +        AV_RB32(p->buf + 4) == AV_RB32("DS16"))
> +        return AVPROBE_SCORE_MAX;
> +    return 0;
> +}
> +
> +static int nsp_read_header(AVFormatContext *s)
> +{
> +    int rate = 0, channels = 0;
> +    uint32_t chunk, size;
> +    AVStream *st;
> +    int64_t pos;
> +
> +    avio_skip(s->pb, 12);
> +    st = avformat_new_stream(s, NULL);
> +    if (!st)
> +        return AVERROR(ENOMEM);
> +
> +    while (!avio_feof(s->pb)) {
> +        chunk = avio_rb32(s->pb);

Not codec_tag?

> +        size  = avio_rl32(s->pb);
> +        pos   = avio_tell(s->pb);
> +
> +        if (chunk == MKBETAG('H', 'D', 'R', '8') ||
> +            chunk == MKBETAG('H', 'E', 'D', 'R')) {

It's your code but I suspect a switch() makes this
more readable.

Carl Eugen