yading@11: /* yading@11: * Tele-typewriter demuxer yading@11: * Copyright (c) 2010 Peter Ross yading@11: * yading@11: * This file is part of FFmpeg. yading@11: * yading@11: * FFmpeg is free software; you can redistribute it and/or yading@11: * modify it under the terms of the GNU Lesser General Public yading@11: * License as published by the Free Software Foundation; either yading@11: * version 2.1 of the License, or (at your option) any later version. yading@11: * yading@11: * FFmpeg is distributed in the hope that it will be useful, yading@11: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@11: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@11: * Lesser General Public License for more details. yading@11: * yading@11: * You should have received a copy of the GNU Lesser General Public yading@11: * License along with FFmpeg; if not, write to the Free Software yading@11: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@11: */ yading@11: yading@11: /** yading@11: * @file yading@11: * Tele-typewriter demuxer yading@11: */ yading@11: yading@11: #include "libavutil/intreadwrite.h" yading@11: #include "libavutil/avstring.h" yading@11: #include "libavutil/log.h" yading@11: #include "libavutil/dict.h" yading@11: #include "libavutil/opt.h" yading@11: #include "libavutil/parseutils.h" yading@11: #include "avformat.h" yading@11: #include "internal.h" yading@11: #include "sauce.h" yading@11: yading@11: typedef struct { yading@11: AVClass *class; yading@11: int chars_per_frame; yading@11: uint64_t fsize; /**< file size less metadata buffer */ yading@11: int width, height; /**< Set by a private option. */ yading@11: AVRational framerate; /**< Set by a private option. */ yading@11: } TtyDemuxContext; yading@11: yading@11: /** yading@11: * Parse EFI header yading@11: */ yading@11: static int efi_read(AVFormatContext *avctx, uint64_t start_pos) yading@11: { yading@11: TtyDemuxContext *s = avctx->priv_data; yading@11: AVIOContext *pb = avctx->pb; yading@11: char buf[37]; yading@11: int len; yading@11: yading@11: avio_seek(pb, start_pos, SEEK_SET); yading@11: if (avio_r8(pb) != 0x1A) yading@11: return -1; yading@11: yading@11: #define GET_EFI_META(name,size) \ yading@11: len = avio_r8(pb); \ yading@11: if (len < 1 || len > size) \ yading@11: return -1; \ yading@11: if (avio_read(pb, buf, size) == size) { \ yading@11: buf[len] = 0; \ yading@11: av_dict_set(&avctx->metadata, name, buf, 0); \ yading@11: } yading@11: yading@11: GET_EFI_META("filename", 12) yading@11: GET_EFI_META("title", 36) yading@11: yading@11: s->fsize = start_pos; yading@11: return 0; yading@11: } yading@11: yading@11: static int read_header(AVFormatContext *avctx) yading@11: { yading@11: TtyDemuxContext *s = avctx->priv_data; yading@11: int ret = 0; yading@11: AVStream *st = avformat_new_stream(avctx, NULL); yading@11: yading@11: if (!st) { yading@11: ret = AVERROR(ENOMEM); yading@11: goto fail; yading@11: } yading@11: st->codec->codec_tag = 0; yading@11: st->codec->codec_type = AVMEDIA_TYPE_VIDEO; yading@11: st->codec->codec_id = AV_CODEC_ID_ANSI; yading@11: yading@11: st->codec->width = s->width; yading@11: st->codec->height = s->height; yading@11: avpriv_set_pts_info(st, 60, s->framerate.den, s->framerate.num); yading@11: st->avg_frame_rate = s->framerate; yading@11: yading@11: /* simulate tty display speed */ yading@11: s->chars_per_frame = FFMAX(av_q2d(st->time_base)*s->chars_per_frame, 1); yading@11: yading@11: if (avctx->pb->seekable) { yading@11: s->fsize = avio_size(avctx->pb); yading@11: st->duration = (s->fsize + s->chars_per_frame - 1) / s->chars_per_frame; yading@11: yading@11: if (ff_sauce_read(avctx, &s->fsize, 0, 0) < 0) yading@11: efi_read(avctx, s->fsize - 51); yading@11: yading@11: avio_seek(avctx->pb, 0, SEEK_SET); yading@11: } yading@11: yading@11: fail: yading@11: return ret; yading@11: } yading@11: yading@11: static int read_packet(AVFormatContext *avctx, AVPacket *pkt) yading@11: { yading@11: TtyDemuxContext *s = avctx->priv_data; yading@11: int n; yading@11: yading@11: if (url_feof(avctx->pb)) yading@11: return AVERROR_EOF; yading@11: yading@11: n = s->chars_per_frame; yading@11: if (s->fsize) { yading@11: // ignore metadata buffer yading@11: uint64_t p = avio_tell(avctx->pb); yading@11: if (p == s->fsize) yading@11: return AVERROR_EOF; yading@11: if (p + s->chars_per_frame > s->fsize) yading@11: n = s->fsize - p; yading@11: } yading@11: yading@11: pkt->size = av_get_packet(avctx->pb, pkt, n); yading@11: if (pkt->size < 0) yading@11: return pkt->size; yading@11: pkt->flags |= AV_PKT_FLAG_KEY; yading@11: return 0; yading@11: } yading@11: yading@11: #define OFFSET(x) offsetof(TtyDemuxContext, x) yading@11: #define DEC AV_OPT_FLAG_DECODING_PARAM yading@11: static const AVOption options[] = { yading@11: { "chars_per_frame", "", offsetof(TtyDemuxContext, chars_per_frame), AV_OPT_TYPE_INT, {.i64 = 6000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM}, yading@11: { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC }, yading@11: { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, DEC }, yading@11: { NULL }, yading@11: }; yading@11: yading@11: static const AVClass tty_demuxer_class = { yading@11: .class_name = "TTY demuxer", yading@11: .item_name = av_default_item_name, yading@11: .option = options, yading@11: .version = LIBAVUTIL_VERSION_INT, yading@11: }; yading@11: yading@11: AVInputFormat ff_tty_demuxer = { yading@11: .name = "tty", yading@11: .long_name = NULL_IF_CONFIG_SMALL("Tele-typewriter"), yading@11: .priv_data_size = sizeof(TtyDemuxContext), yading@11: .read_header = read_header, yading@11: .read_packet = read_packet, yading@11: .extensions = "ans,art,asc,diz,ice,nfo,txt,vt", yading@11: .priv_class = &tty_demuxer_class, yading@11: };