Quoting Vittorio Giovara (2014-11-23 23:59:25)
> From: Oleksij Rempel <[email protected]>
>
> Signed-off-by: Oleksij Rempel <[email protected]>
> Signed-off-by: Luca Barbato <[email protected]>
> Signed-off-by: Vittorio Giovara <[email protected]>
> ---
> Changelog and version bump.
> Vittorio
>
> Changelog | 2 +-
> libavformat/Makefile | 1 +
> libavformat/allformats.c | 1 +
> libavformat/dss.c | 326
> +++++++++++++++++++++++++++++++++++++++++++++++
> libavformat/version.h | 2 +-
> 5 files changed, 330 insertions(+), 2 deletions(-)
> create mode 100644 libavformat/dss.c
>
> diff --git a/Changelog b/Changelog
> index 49bd12e..e4515e8 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -7,7 +7,7 @@ version <next>:
> - avplay now exits by default at the end of playback
> - XCB-based screen-grabber
> - creating DASH compatible fragmented MP4, MPEG-DASH segmenting muxer
> -- DSS decoder (sp/lp)
> +- DSS decoder (sp/lp) and demuxer
>
>
> version 11:
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 15f205a..5e1b29c 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -100,6 +100,7 @@ OBJS-$(CONFIG_DIRAC_MUXER) += rawenc.o
> OBJS-$(CONFIG_DNXHD_DEMUXER) += dnxhddec.o rawdec.o
> OBJS-$(CONFIG_DNXHD_MUXER) += rawenc.o
> OBJS-$(CONFIG_DSICIN_DEMUXER) += dsicin.o
> +OBJS-$(CONFIG_DSS_DEMUXER) += dss.o
> OBJS-$(CONFIG_DTS_DEMUXER) += dtsdec.o rawdec.o
> OBJS-$(CONFIG_DTS_MUXER) += rawenc.o
> OBJS-$(CONFIG_DV_DEMUXER) += dv.o
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index 7868e3e..7b425be 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -94,6 +94,7 @@ void av_register_all(void)
> REGISTER_MUXDEMUX(DIRAC, dirac);
> REGISTER_MUXDEMUX(DNXHD, dnxhd);
> REGISTER_DEMUXER (DSICIN, dsicin);
> + REGISTER_DEMUXER (DSS, dss);
> REGISTER_MUXDEMUX(DTS, dts);
> REGISTER_MUXDEMUX(DV, dv);
> REGISTER_DEMUXER (DXA, dxa);
> diff --git a/libavformat/dss.c b/libavformat/dss.c
> new file mode 100644
> index 0000000..8d0896a
> --- /dev/null
> +++ b/libavformat/dss.c
> @@ -0,0 +1,326 @@
> +/*
> + * dss demuxer
> + * Copyright (c) 2014 Oleksij Rempel <[email protected]>
> + *
> + * This file is part of Libav.
> + *
> + * Libav 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.
> + *
> + * Libav 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 Libav; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
> USA
> + */
> +
> +#include "libavutil/bswap.h"
> +#include "libavutil/intreadwrite.h"
> +#include "libavutil/attributes.h"
> +#include "libavutil/channel_layout.h"
> +#include "avformat.h"
> +#include "internal.h"
> +
> +#define DSS_HEAD_OFFSET_AUTHOR 0xc
> +#define DSS_AUTHOR_SIZE 16
> +
> +#define DSS_HEAD_OFFSET_START_TIME 0x26
> +#define DSS_HEAD_OFFSET_END_TIME 0x32
> +#define DSS_TIME_SIZE 12
> +
> +#define DSS_HEAD_OFFSET_ACODEC 0x2a4
> +#define DSS_ACODEC_DSS_SP 0x0 /* SP mode */
> +#define DSS_ACODEC_G723_1 0x2 /* LP mode */
> +
> +#define DSS_HEAD_OFFSET_COMMENT 0x31e
> +#define DSS_COMMENT_SIZE 64
> +
> +#define DSS_BLOCK_SIZE 512
> +#define DSS_HEADER_SIZE (DSS_BLOCK_SIZE * 2)
> +#define DSS_AUDIO_BLOCK_HEADER_SIZE 6
> +#define DSS_SP_FRAME_SIZE 42
> +
> +static const uint8_t frame_size[4] = { 24, 20, 4, 1 };
> +
> +typedef struct DSSDemuxContext {
> + unsigned int audio_codec;
> + int counter;
> + int swap;
> + int dsssp_swap_byte;
> +} DSSDemuxContext;
> +
> +static int dss_probe(AVProbeData *p)
> +{
> + /* Magic is 'DSS' */
> + if (*p->buf != 0x02 || *(p->buf + 1) != 'D' || *(p->buf + 2) != 'S' ||
> + *(p->buf + 3) != 'S')
> + return 0;
> +
> + return AVPROBE_SCORE_MAX;
> +}
> +
> +static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
This return value is not checked. Same below.
> + const char *key)
Broken alignment. Ditto.
> +{
> + AVIOContext *pb = s->pb;
> + char string[DSS_TIME_SIZE], datetime[64];
> + int y, month, d, h, minute, sec;
> + int ret;
> +
> + avio_seek(pb, offset, SEEK_SET);
> +
> + ret = avio_read(s->pb, string, DSS_TIME_SIZE);
> + if (ret < DSS_TIME_SIZE)
> + return ret < 0 ? ret : AVERROR_EOF;
> +
> + sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec);
> + /* We deal here with two digit year, so set default date to 2000
> + * and hope it will never be used in next century
> + */
> + snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
> + y + 2000, month, d, h, minute, sec);
> + av_dict_set(&s->metadata, key, datetime, 0);
> +
> + return ret;
> +}
> +
> +static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset,
> + unsigned int size, const char *key)
> +{
> + AVIOContext *pb = s->pb;
> + char *value;
> + int ret;
> +
> + avio_seek(pb, offset, SEEK_SET);
> +
> + value = av_malloc(size + 1);
> + if (!value)
> + return AVERROR(ENOMEM);
> + /*make sure, string will end with \0 */
> + *(value + size) = '\0';
> +
> + ret = avio_read(s->pb, value, size);
> + av_dict_set(&s->metadata, key, value, 0);
> +
> + av_free(value);
> + if (ret < size)
> + return ret < 0 ? ret : AVERROR_EOF;
> +
> + return ret;
> +}
> +
> +static int dss_read_header(AVFormatContext *s)
> +{
> + DSSDemuxContext *priv = s->priv_data;
> + AVStream *st;
> + AVIOContext *pb = s->pb;
> +
> + if (avio_size(pb) <= DSS_HEADER_SIZE)
> + return AVERROR(EINVAL);
You should not do this. If the format does not require you to seek
backwards (which it apparently does not), the demuxer should handle
non-seekable inputs as well.
> +
> + st = avformat_new_stream(s, NULL);
> + if (!st)
> + return AVERROR(ENOMEM);
> +
> + dss_read_metadata_string(s, DSS_HEAD_OFFSET_AUTHOR,
> + DSS_AUTHOR_SIZE, "author");
> + dss_read_metadata_date(s, DSS_HEAD_OFFSET_END_TIME, "date");
> +
> + dss_read_metadata_string(s, DSS_HEAD_OFFSET_COMMENT,
> + DSS_COMMENT_SIZE, "comment");
> +
> + avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
> + priv->audio_codec = avio_r8(pb);
> +
> + if (priv->audio_codec == DSS_ACODEC_DSS_SP) {
> + st->codec->codec_id = AV_CODEC_ID_DSS_SP;
> + st->codec->sample_rate = 12000;
> + } else if (priv->audio_codec == DSS_ACODEC_G723_1) {
> + st->codec->codec_id = AV_CODEC_ID_G723_1;
> + st->codec->sample_rate = 8000;
> + } else {
> + avpriv_request_sample(s, "Support for codec %x in DSS",
> + priv->audio_codec);
> + return AVERROR_PATCHWELCOME;
> + }
> +
> + st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
> + st->codec->channel_layout = AV_CH_LAYOUT_MONO;
> + st->codec->channels = 1;
> +
> + avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
> + st->start_time = 0;
> +
> + /* Jump over header */
> +
> + if (avio_seek(pb, DSS_HEADER_SIZE, SEEK_SET) != DSS_HEADER_SIZE)
> + return AVERROR(EIO);
> +
> + priv->counter = 0;
> + priv->swap = 0;
> +
> + return 0;
> +}
> +
> +static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
> +{
> + DSSDemuxContext *priv = s->priv_data;
> + AVIOContext *pb = s->pb;
> +
> + avio_skip(pb, DSS_AUDIO_BLOCK_HEADER_SIZE);
> + priv->counter += DSS_BLOCK_SIZE - DSS_AUDIO_BLOCK_HEADER_SIZE;
> +}
> +
> +static void dss_sp_byte_swap(DSSDemuxContext *priv,
> + int8_t *dst, const int8_t *src)
> +{
> + int i;
> +
> + if (priv->swap) {
> + for (i = 3; i < DSS_SP_FRAME_SIZE - 2; i += 2)
> + dst[i] = src[i];
> +
> + for (i = 0; i < DSS_SP_FRAME_SIZE - 2; i += 2)
> + dst[i] = src[i + 4];
> +
> + dst[1] = priv->dsssp_swap_byte;
> + } else {
> + memcpy(dst, src, DSS_SP_FRAME_SIZE);
> + priv->dsssp_swap_byte = src[DSS_SP_FRAME_SIZE - 2];
> + }
> +
> + /* make sure byte 40 is always 0 */
> + dst[DSS_SP_FRAME_SIZE - 2] = 0;
> + priv->swap ^= 1;
> +}
> +
> +static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> + DSSDemuxContext *priv = s->priv_data;
> + int read_size, ret, offset = 0, buff_offset = 0;
> + int8_t *buff;
> +
> + if (priv->counter == 0)
> + dss_skip_audio_header(s, pkt);
> +
> + pkt->pos = avio_tell(s->pb);
> +
> + if (priv->swap) {
> + read_size = DSS_SP_FRAME_SIZE - 2;
> + buff_offset = 3;
> + } else
> + read_size = DSS_SP_FRAME_SIZE;
> +
> + priv->counter -= read_size;
> +
> + buff = av_malloc(DSS_SP_FRAME_SIZE + 1);
> + if (!buff)
> + return AVERROR_EOF;
> +
> + ret = av_new_packet(pkt, DSS_SP_FRAME_SIZE);
> + if (ret < 0)
Leaking buff. Also, why allocate it for every packet. The size is
constant, just keep it in the context.
--
Anton Khirnov
_______________________________________________
libav-devel mailing list
[email protected]
https://lists.libav.org/mailman/listinfo/libav-devel
