[FFmpeg-devel] [PATCH] Lego Mindstorms RSO de/muxer (copied from au.c)

Stefano Sabatini stefano.sabatini-lala
Fri Jul 16 15:52:10 CEST 2010


On date Thursday 2010-07-15 16:44:49 +0200, Rafa?l Carr? encoded:
[...]
> From cd28136c6c73cc3aba5cd29a3eb5216dbda8113b Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Rafa=C3=ABl=20Carr=C3=A9?= <rafael.carre at gmail.com>
> Date: Wed, 14 Jul 2010 21:36:33 +0200
> Subject: [PATCH] Lego Mindstorms RSO de/muxer (copied from au.c)
> 
> - format from http://bricxcc.sourceforge.net/
> 
> - TODO: IMA ADPCM, it seems to be the CODEC_ID_ADPCM_IMA_WAV codec, but
>   predictor/step are not passed in the bitstream.
>   I sent a sample to Kostya, if he finds the (fixed for RSO) parameters,
>   we could put them in extradata and check if extradata is present in
>   the decoder.
> 
> - Totally untested on reference implementation (i didn't have/play Lego
>   for years), but demuxing/remuxing gives the same output.
> 
> - Probe the file format based on known codec IDs and guessed possible
>   values for loop flag (0 or 1)
>   I've found files with sampling rate of 3000Hz, and guessed an upper
>   bound of 16kHz which looks acceptable given the very limited file size
>   typically used with this format
> 
> Note: file size is limited to 65535 bytes + 8 bytes header (output is
> stored on a ~128kB flash, probably together with code)
> ---
>  Changelog                |    1 +
>  doc/general.texi         |    1 +
>  libavformat/Makefile     |    2 +
>  libavformat/allformats.c |    1 +
>  libavformat/avformat.h   |    2 +-
>  libavformat/rso.h        |   36 ++++++++++++++
>  libavformat/rsodec.c     |  119 ++++++++++++++++++++++++++++++++++++++++++++++
>  libavformat/rsoenc.c     |  115 ++++++++++++++++++++++++++++++++++++++++++++
>  8 files changed, 276 insertions(+), 1 deletions(-)
>  create mode 100644 libavformat/rso.h
>  create mode 100644 libavformat/rsodec.c
>  create mode 100644 libavformat/rsoenc.c
> 
> diff --git a/Changelog b/Changelog
> index 6a04869..d408942 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -21,6 +21,7 @@ version <next>:
>  - ffplay -exitonkeydown and -exitonmousedown options added
>  - native GSM / GSM MS decoder
>  - RTP depacketization of QDM2
> +- Lego Mindstorms RSO de/muxer
>  
>  
>  
> diff --git a/doc/general.texi b/doc/general.texi
> index 3a1fb7c..67cf2c4 100644
> --- a/doc/general.texi
> +++ b/doc/general.texi
> @@ -209,6 +209,7 @@ library:
>  @item RL2                       @tab   @tab X
>      @tab Audio and video format used in some games by Entertainment Software Partners.
>  @item RPL/ARMovie               @tab   @tab X
> + at item Lego Mindstorms RSO       @tab X @tab X
>  @item RTMP                      @tab X @tab X
>      @tab Output is performed by publishing stream to RTMP server
>  @item RTP                       @tab   @tab X
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index cab222c..317d113 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -209,6 +209,8 @@ OBJS-$(CONFIG_RM_DEMUXER)                += rmdec.o rm.o
>  OBJS-$(CONFIG_RM_MUXER)                  += rmenc.o rm.o
>  OBJS-$(CONFIG_ROQ_DEMUXER)               += idroq.o
>  OBJS-$(CONFIG_ROQ_MUXER)                 += raw.o
> +OBJS-$(CONFIG_RSO_DEMUXER)               += rsodec.o raw.o
> +OBJS-$(CONFIG_RSO_MUXER)                 += rsoenc.o
>  OBJS-$(CONFIG_RPL_DEMUXER)               += rpl.o
>  OBJS-$(CONFIG_RTP_MUXER)                 += rtp.o         \
>                                              rtpenc_aac.o     \
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index 94ab78c..66aab6e 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -174,6 +174,7 @@ void av_register_all(void)
>      REGISTER_MUXDEMUX (RM, rm);
>      REGISTER_MUXDEMUX (ROQ, roq);
>      REGISTER_DEMUXER  (RPL, rpl);
> +    REGISTER_MUXDEMUX (RSO, rso);
>      REGISTER_MUXER    (RTP, rtp);
>      REGISTER_MUXDEMUX (RTSP, rtsp);
>      REGISTER_DEMUXER  (SDP, sdp);
> diff --git a/libavformat/avformat.h b/libavformat/avformat.h
> index 7d7fce8..4ab5cb5 100644
> --- a/libavformat/avformat.h
> +++ b/libavformat/avformat.h
> @@ -22,7 +22,7 @@
>  #define AVFORMAT_AVFORMAT_H
>  
>  #define LIBAVFORMAT_VERSION_MAJOR 52
> -#define LIBAVFORMAT_VERSION_MINOR 73
> +#define LIBAVFORMAT_VERSION_MINOR 74
>  #define LIBAVFORMAT_VERSION_MICRO  0
>  
>  #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
> diff --git a/libavformat/rso.h b/libavformat/rso.h
> new file mode 100644
> index 0000000..6e1a313
> --- /dev/null
> +++ b/libavformat/rso.h
> @@ -0,0 +1,36 @@
> +/*
> + * RSO format common data
> + * Copyright (c) 2010 Rafael Carre
> + *
> + * 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
> + */
> +
> +#ifndef AVFORMAT_RSO_H
> +#define AVFORMAT_RSO_H
> +
> +#include "avformat.h"
> +
> +#define RSO_HEADER_SIZE 8
> +
> +/* The ffmpeg codecs we support, and the IDs they have in the file */
> +static const AVCodecTag codec_rso_tags[] = {
> +    { CODEC_ID_PCM_U8,          0x0100 },
> +    { CODEC_ID_ADPCM_IMA_WAV,   0x0101 },
> +    { CODEC_ID_NONE, 0 },
> +};
> +
> +#endif /* AVFORMAT_RSO_H */
> diff --git a/libavformat/rsodec.c b/libavformat/rsodec.c
> new file mode 100644
> index 0000000..5a2fcc2
> --- /dev/null
> +++ b/libavformat/rsodec.c
> @@ -0,0 +1,119 @@
> +/*
> + * RSO demuxer
> + * Copyright (c) 2001 Fabrice Bellard (original AU code)
> + * Copyright (c) 2010 Rafael Carre
> + *
> + * 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/intreadwrite.h"
> +#include "avformat.h"
> +#include "raw.h"
> +#include "riff.h"
> +#include "rso.h"
> +
> +static int rso_probe(AVProbeData *p)
> +{
> +    uint16_t rate, loop;
> +
> +    if (p->buf_size < RSO_HEADER_SIZE)
> +        return 0;
> +
> +    if (ff_codec_get_id(codec_rso_tags, AV_RB16(&p->buf[0])) == CODEC_ID_NONE)
> +        return 0;
> +
> +    rate = AV_RB16(&p->buf[4]);
> +    if (rate < 3000 || rate > 16000)        /* XXX: find legal sample rates */
> +        return 0;
> +
> +    loop = AV_RB16(&p->buf[6]);
> +    if (loop != 0x0000 && loop != 0x0001)   /* XXX: find legal values */
> +        return 0;
> +
> +    /* we have no magic value for reliable probing, return half of max score. */
> +    return AVPROBE_SCORE_MAX / 2;
> +}
> +
> +static int rso_read_header(AVFormatContext *s, AVFormatParameters *ap)
> +{
> +    ByteIOContext *pb = s->pb;
> +    unsigned int id, rate, size, bpp;
> +    enum CodecID codec;
> +    AVStream *st;
> +
> +    id =    get_be16(pb);
> +    size =  get_be16(pb);
> +    rate =  get_be16(pb);
> +
> +    get_be16(pb);   /* play mode ? (0x0000 = don't loop) */
> +
> +    codec = ff_codec_get_id(codec_rso_tags, id);
> +
> +    if (codec == CODEC_ID_ADPCM_IMA_WAV) {
> +        av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
> +        return -1;

AVPATCH_WELCOME or AVERROR(EINVAL) if you don't want patches.

  }
> +
> +    bpp = av_get_bits_per_sample(codec);
> +    if (!bpp) {
> +        av_log_ask_for_sample(s, "could not determine bits per sample\n");
> +        return AVERROR_INVALIDDATA;
> +    }
> +
> +    /* now we are ready: build format streams */
> +    st = av_new_stream(s, 0);
> +    if (!st)
> +        return -1;

AVERROR(ENOMEM).

> +    st->duration = size << 3 / bpp;
> +    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
> +    st->codec->codec_tag = id;
> +    st->codec->codec_id = codec;
> +    st->codec->channels = 1;
> +    st->codec->sample_rate = rate;
> +    av_set_pts_info(st, 64, 1, rate);
> +    return 0;
> +}
> +
> +#define BLOCK_SIZE 1024
> +
> +static int rso_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> +    int bpp = av_get_bits_per_sample(s->streams[0]->codec->codec_id);
> +    int ret = av_get_packet(s->pb, pkt, BLOCK_SIZE * bpp >> 3);
> +
> +    if (ret < 0)
> +        return ret;
> +
> +    pkt->stream_index = 0;
> +
> +    /* note: we need to modify the packet size here to handle the last packet */
> +    pkt->size = ret;
> +
> +    return 0;
> +}
> +
> +AVInputFormat rso_demuxer = {
> +    .name           =   "rso",
> +    .long_name      =   NULL_IF_CONFIG_SMALL("Lego Mindstorms RSO format"),
> +    .priv_data_size =   0,
> +    .read_probe     =   rso_probe,
> +    .read_header    =   rso_read_header,
> +    .read_packet    =   rso_read_packet,
> +    .read_close     =   NULL,
> +    .read_seek      =   pcm_read_seek,
> +    .codec_tag      =   (const AVCodecTag* const []){codec_rso_tags, 0},
> +};
> diff --git a/libavformat/rsoenc.c b/libavformat/rsoenc.c
> new file mode 100644
> index 0000000..7a33b0f
> --- /dev/null
> +++ b/libavformat/rsoenc.c
> @@ -0,0 +1,115 @@
> +/*
> + * RSO muxer
> + * Copyright (c) 2001 Fabrice Bellard (original AU code)
> + * Copyright (c) 2010 Rafael Carre
> + *
> + * 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 "avformat.h"
> +#include "riff.h"
> +#include "rso.h"
> +

> +static int rso_write_header(AVFormatContext *s)
> +{
> +    ByteIOContext  *pb  = s->pb;
> +    AVCodecContext *enc = s->streams[0]->codec;
> +
> +    if (!enc->codec_tag)
> +        return -1;
> +
> +    if (enc->channels != 1) {
> +        av_log(s, AV_LOG_ERROR, "RSO only supports mono\n");
> +        return -1;
> +    }
> +
> +    if (url_is_streamed(s->pb)) {
> +        av_log(s, AV_LOG_ERROR, "muxer does not support non seekable output\n");
> +        return -1;
> +    }
> +
> +    /* XXX: find legal sample rates */
> +    if (enc->sample_rate >= 1u<<16) {
> +        av_log(s, AV_LOG_ERROR, "Sample rate must be < 65536\n");
> +        return -1;
> +    }
> +
> +    if (enc->codec_id == CODEC_ID_ADPCM_IMA_WAV) {
> +        av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
> +        return -1;
> +    }

Similarly please use meaningful error codes.

Regards.



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