diff options
author | Peter Ross <pross@xvid.org> | 2010-07-18 12:06:55 +0400 |
---|---|---|
committer | Peter Ross <pross@xvid.org> | 2010-07-18 12:06:55 +0400 |
commit | 5a717094676a9c3a5bc67686cb369911922cdd82 (patch) | |
tree | e5100336f6b0f517f1cf23550c9da7b19159cd0f /libavformat/tty.c | |
parent | 0459bf2d02a0c53c334354f3a0d30de68458dae2 (diff) |
Tele-typewriter demuxer
Originally committed as revision 24301 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavformat/tty.c')
-rw-r--r-- | libavformat/tty.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/libavformat/tty.c b/libavformat/tty.c new file mode 100644 index 0000000000..03a4f16d76 --- /dev/null +++ b/libavformat/tty.c @@ -0,0 +1,131 @@ +/* + * @file + * Tele-typewriter demuxer + * Copyright (c) 2010 Peter Ross <pross@xvid.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 "libavutil/intreadwrite.h" +#include "libavutil/avstring.h" +#include "avformat.h" +#include "sauce.h" +#include <strings.h> + +#define LINE_RATE 6000 /* characters per second */ + +typedef struct { + int chars_per_frame; + uint64_t fsize; /** file size less metadata buffer */ +} TtyDemuxContext; + +/** + * Parse EFI header + */ +static int efi_read(AVFormatContext *avctx, uint64_t start_pos) +{ + TtyDemuxContext *s = avctx->priv_data; + ByteIOContext *pb = avctx->pb; + char buf[37]; + int len; + + url_fseek(pb, start_pos, SEEK_SET); + if (get_byte(pb) != 0x1A) + return -1; + +#define GET_EFI_META(name,size) \ + len = get_byte(pb); \ + if (len < 1 || len > size) \ + return -1; \ + if (get_buffer(pb, buf, size) == size) { \ + buf[len] = 0; \ + av_metadata_set2(&avctx->metadata, name, buf, 0); \ + } + + GET_EFI_META("filename", 12) + GET_EFI_META("title", 36) + + s->fsize = start_pos; + return 0; +} + +static int read_header(AVFormatContext *avctx, + AVFormatParameters *ap) +{ + TtyDemuxContext *s = avctx->priv_data; + AVStream *st = av_new_stream(avctx, 0); + if (!st) + return AVERROR(ENOMEM); + st->codec->codec_tag = 0; + st->codec->codec_type = CODEC_TYPE_VIDEO; + st->codec->codec_id = CODEC_ID_ANSI; + if (ap->width) st->codec->width = ap->width; + if (ap->height) st->codec->height = ap->height; + + if (!ap->time_base.num) { + av_set_pts_info(st, 60, 1, 25); + } else { + av_set_pts_info(st, 60, ap->time_base.num, ap->time_base.den); + } + + /* simulate tty display speed */ + s->chars_per_frame = FFMAX(av_q2d(st->time_base) * (ap->sample_rate ? ap->sample_rate : LINE_RATE), 1); + + if (!url_is_streamed(avctx->pb)) { + s->fsize = url_fsize(avctx->pb); + st->duration = (s->fsize + s->chars_per_frame - 1) / s->chars_per_frame; + + if (ff_sauce_read(avctx, &s->fsize, 0, 0) < 0) + efi_read(avctx, s->fsize - 51); + + url_fseek(avctx->pb, 0, SEEK_SET); + } + + return 0; +} + +static int read_packet(AVFormatContext *avctx, AVPacket *pkt) +{ + TtyDemuxContext *s = avctx->priv_data; + int n; + + if (url_feof(avctx->pb)) + return AVERROR_EOF; + + n = s->chars_per_frame; + if (s->fsize) { + // ignore metadata buffer + uint64_t p = url_ftell(avctx->pb); + if (p + s->chars_per_frame > s->fsize) + n = s->fsize - p; + } + + pkt->size = av_get_packet(avctx->pb, pkt, n); + if (pkt->size <= 0) + return AVERROR(EIO); + pkt->flags |= PKT_FLAG_KEY; + return 0; +} + +AVInputFormat tty_demuxer = { + .name = "tty", + .long_name = NULL_IF_CONFIG_SMALL("Tele-typewriter"), + .priv_data_size = sizeof(TtyDemuxContext), + .read_header = read_header, + .read_packet = read_packet, + .extensions = "ans,art,asc,diz,ice,nfo,txt,vt", +}; |