[FFmpeg-devel] [PATCH 1/2] avformat: add binka demuxer

[Andreas Rheinhardt]

James Almer:
> On 2/2/2021 9:40 PM, Paul B Mahol wrote:
>> Signed-off-by: Paul B Mahol <onemda at gmail.com>
>> ---
>>   libavformat/Makefile     |   1 +
>>   libavformat/allformats.c |   1 +
>>   libavformat/binka.c      | 107 +++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 109 insertions(+)
>>   create mode 100644 libavformat/binka.c
>>
>> diff --git a/libavformat/Makefile b/libavformat/Makefile
>> index 85f432c8d9..b977fa0b1e 100644
>> --- a/libavformat/Makefile
>> +++ b/libavformat/Makefile
>> @@ -131,6 +131,7 @@ OBJS-$(CONFIG_AVS3_DEMUXER)              +=
>> avs3dec.o rawdec.o
>>   OBJS-$(CONFIG_BETHSOFTVID_DEMUXER)       += bethsoftvid.o
>>   OBJS-$(CONFIG_BFI_DEMUXER)               += bfi.o
>>   OBJS-$(CONFIG_BINK_DEMUXER)              += bink.o
>> +OBJS-$(CONFIG_BINKA_DEMUXER)             += binka.o
>>   OBJS-$(CONFIG_BINTEXT_DEMUXER)           += bintext.o sauce.o
>>   OBJS-$(CONFIG_BIT_DEMUXER)               += bit.o
>>   OBJS-$(CONFIG_BIT_MUXER)                 += bit.o
>> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
>> index 6990af55f4..9628c726a7 100644
>> --- a/libavformat/allformats.c
>> +++ b/libavformat/allformats.c
>> @@ -94,6 +94,7 @@ extern AVInputFormat  ff_bethsoftvid_demuxer;
>>   extern AVInputFormat  ff_bfi_demuxer;
>>   extern AVInputFormat  ff_bintext_demuxer;
>>   extern AVInputFormat  ff_bink_demuxer;
>> +extern AVInputFormat  ff_binka_demuxer;
>>   extern AVInputFormat  ff_bit_demuxer;
>>   extern AVOutputFormat ff_bit_muxer;
>>   extern AVInputFormat  ff_bmv_demuxer;
>> diff --git a/libavformat/binka.c b/libavformat/binka.c
>> new file mode 100644
>> index 0000000000..5ed0f17968
>> --- /dev/null
>> +++ b/libavformat/binka.c
>> @@ -0,0 +1,107 @@
>> +/*
>> + * Copyright (c) 2021 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/intreadwrite.h"
>> +#include "avformat.h"
>> +#include "internal.h"
>> +
>> +static int binka_probe(const AVProbeData *p)
>> +{
>> +    if (AV_RB32(p->buf) == MKBETAG('1', 'F', 'C', 'B'))
>> +        return AVPROBE_SCORE_MAX;
>> +    return 0;
>> +}
>> +
>> +static int binka_read_header(AVFormatContext *s)
>> +{
>> +    AVIOContext *pb = s->pb;
>> +    AVStream *st;
>> +    uint32_t samples;
>> +    int entries;
>> +    int64_t offset;
>> +    int ret;
>> +
>> +    st = avformat_new_stream(s, NULL);
>> +    if (!st)
>> +        return AVERROR(ENOMEM);
>> +
>> +    avio_skip(pb, 5);
>> +
>> +    st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
>> +    st->codecpar->codec_id = AV_CODEC_ID_BINKAUDIO_DCT;
>> +    st->codecpar->channels = avio_r8(pb);
>> +    st->codecpar->sample_rate = avio_rl16(pb);
>> +    st->duration = avio_rl32(pb);
>> +
>> +    avio_skip(pb, 4);
>> +    samples = avio_rl32(pb);
>> +    entries = avio_rl16(pb);
> 
> Is this a seek table? Why are you not using it?
> 
>> +
>> +    if ((ret = ff_get_extradata(s, st->codecpar, pb, 2)) < 0)
>> +        return ret;
>> +
>> +    offset = entries * 2;
>> +    avio_skip(pb, offset);
>> +
>> +    avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
>> +
>> +    s->internal->data_offset = avio_tell(pb);
>> +
>> +    return 0;
>> +}
>> +
>> +static int binka_read_packet(AVFormatContext *s, AVPacket *pkt)
>> +{
>> +    AVIOContext *pb = s->pb;
>> +    int64_t pos;
>> +    int pkt_size;
>> +    int ret;
>> +
>> +    if (avio_feof(pb))
>> +        return AVERROR_EOF;
>> +
>> +    pos = avio_tell(pb);
>> +    avio_skip(pb, 2);
>> +    pkt_size = avio_rl16(pb) + 4;
>> +    if (pkt_size <= 4)
>> +        return AVERROR(EIO);
> 
>> +    ret = av_new_packet(pkt, pkt_size);
>> +    if (ret < 0)
>> +        return ret;
>> +
>> +    avio_read(pb, pkt->data + 4, pkt_size - 4);
> 
> av_get_packet()
> 

Doesn't work when you want the data read to be put somewhere else than
the beginning of the packet.

>> +    AV_WL32(pkt->data, pkt_size);
>> +
>> +    pkt->pos = pos;
>> +    pkt->stream_index = 0;
>> +    pkt->flags |= AV_PKT_FLAG_KEY;
> 
> Timestamps and duration?
> 
>> +
>> +    return 0;
>> +}
>> +
>> +AVInputFormat ff_binka_demuxer = {
>> +    .name           = "binka",
>> +    .long_name      = NULL_IF_CONFIG_SMALL("Bink Audio"),
>> +    .read_probe     = binka_probe,
>> +    .read_header    = binka_read_header,
>> +    .read_packet    = binka_read_packet,
>> +    .flags          = AVFMT_GENERIC_INDEX,
>> +    .extensions     = "binka",
>> +};
>>
>