diff options
Diffstat (limited to 'ffmpeg/libavformat/tty.c')
| -rw-r--r-- | ffmpeg/libavformat/tty.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/ffmpeg/libavformat/tty.c b/ffmpeg/libavformat/tty.c new file mode 100644 index 0000000..9b3fa0a --- /dev/null +++ b/ffmpeg/libavformat/tty.c @@ -0,0 +1,169 @@ +/* + * 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 + */ + +/** + * @file + * Tele-typewriter demuxer + */ + +#include "libavutil/intreadwrite.h" +#include "libavutil/avstring.h" +#include "libavutil/log.h" +#include "libavutil/dict.h" +#include "libavutil/opt.h" +#include "libavutil/parseutils.h" +#include "avformat.h" +#include "internal.h" +#include "sauce.h" + +typedef struct { + AVClass *class; + int chars_per_frame; + uint64_t fsize; /**< file size less metadata buffer */ + char *video_size;/**< A string describing video size, set by a private option. */ + char *framerate; /**< Set by a private option. */ +} TtyDemuxContext; + +/** + * Parse EFI header + */ +static int efi_read(AVFormatContext *avctx, uint64_t start_pos) +{ + TtyDemuxContext *s = avctx->priv_data; + AVIOContext *pb = avctx->pb; + char buf[37]; + int len; + + avio_seek(pb, start_pos, SEEK_SET); + if (avio_r8(pb) != 0x1A) + return -1; + +#define GET_EFI_META(name,size) \ + len = avio_r8(pb); \ + if (len < 1 || len > size) \ + return -1; \ + if (avio_read(pb, buf, size) == size) { \ + buf[len] = 0; \ + av_dict_set(&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) +{ + TtyDemuxContext *s = avctx->priv_data; + int width = 0, height = 0, ret = 0; + AVStream *st = avformat_new_stream(avctx, NULL); + AVRational framerate; + + if (!st) { + ret = AVERROR(ENOMEM); + goto fail; + } + st->codec->codec_tag = 0; + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_ANSI; + + if (s->video_size && (ret = av_parse_video_size(&width, &height, s->video_size)) < 0) { + av_log (avctx, AV_LOG_ERROR, "Couldn't parse video size.\n"); + goto fail; + } + if ((ret = av_parse_video_rate(&framerate, s->framerate)) < 0) { + av_log(avctx, AV_LOG_ERROR, "Could not parse framerate: %s.\n", s->framerate); + goto fail; + } + st->codec->width = width; + st->codec->height = height; + avpriv_set_pts_info(st, 60, framerate.den, framerate.num); + st->avg_frame_rate = framerate; + + /* simulate tty display speed */ + s->chars_per_frame = FFMAX(av_q2d(st->time_base)*s->chars_per_frame, 1); + + if (avctx->pb->seekable) { + s->fsize = avio_size(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); + + avio_seek(avctx->pb, 0, SEEK_SET); + } + +fail: + return ret; +} + +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 = avio_tell(avctx->pb); + if (p == s->fsize) + return AVERROR_EOF; + 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 pkt->size; + pkt->flags |= AV_PKT_FLAG_KEY; + return 0; +} + +#define OFFSET(x) offsetof(TtyDemuxContext, x) +#define DEC AV_OPT_FLAG_DECODING_PARAM +static const AVOption options[] = { + { "chars_per_frame", "", offsetof(TtyDemuxContext, chars_per_frame), AV_OPT_TYPE_INT, {.i64 = 6000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM}, + { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC }, + { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0, DEC }, + { NULL }, +}; + +static const AVClass tty_demuxer_class = { + .class_name = "TTY demuxer", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_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", + .priv_class = &tty_demuxer_class, +}; |