diff options
Diffstat (limited to 'ffmpeg/libavformat/rtpdec_asf.c')
| -rw-r--r-- | ffmpeg/libavformat/rtpdec_asf.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/ffmpeg/libavformat/rtpdec_asf.c b/ffmpeg/libavformat/rtpdec_asf.c new file mode 100644 index 0000000..35603f2 --- /dev/null +++ b/ffmpeg/libavformat/rtpdec_asf.c @@ -0,0 +1,310 @@ +/* + * Microsoft RTP/ASF support. + * Copyright (c) 2008 Ronald S. Bultje + * + * 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 + * @brief Microsoft RTP/ASF support + * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net> + */ + +#include "libavutil/base64.h" +#include "libavutil/avstring.h" +#include "libavutil/intreadwrite.h" +#include "rtp.h" +#include "rtpdec_formats.h" +#include "rtsp.h" +#include "asf.h" +#include "avio_internal.h" +#include "internal.h" + +/** + * From MSDN 2.2.1.4, we learn that ASF data packets over RTP should not + * contain any padding. Unfortunately, the header min/max_pktsize are not + * updated (thus making min_pktsize invalid). Here, we "fix" these faulty + * min_pktsize values in the ASF file header. + * @return 0 on success, <0 on failure (currently -1). + */ +static int rtp_asf_fix_header(uint8_t *buf, int len) +{ + uint8_t *p = buf, *end = buf + len; + + if (len < sizeof(ff_asf_guid) * 2 + 22 || + memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) { + return -1; + } + p += sizeof(ff_asf_guid) + 14; + do { + uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid)); + if (memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) { + if (chunksize > end - p) + return -1; + p += chunksize; + continue; + } + + /* skip most of the file header, to min_pktsize */ + p += 6 * 8 + 3 * 4 + sizeof(ff_asf_guid) * 2; + if (p + 8 <= end && AV_RL32(p) == AV_RL32(p + 4)) { + /* and set that to zero */ + AV_WL32(p, 0); + return 0; + } + break; + } while (end - p >= sizeof(ff_asf_guid) + 8); + + return -1; +} + +/** + * The following code is basically a buffered AVIOContext, + * with the added benefit of returning -EAGAIN (instead of 0) + * on packet boundaries, such that the ASF demuxer can return + * safely and resume business at the next packet. + */ +static int packetizer_read(void *opaque, uint8_t *buf, int buf_size) +{ + return AVERROR(EAGAIN); +} + +static void init_packetizer(AVIOContext *pb, uint8_t *buf, int len) +{ + ffio_init_context(pb, buf, len, 0, NULL, packetizer_read, NULL, NULL); + + /* this "fills" the buffer with its current content */ + pb->pos = len; + pb->buf_end = buf + len; +} + +int ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p) +{ + int ret = 0; + if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p)) { + AVIOContext pb; + RTSPState *rt = s->priv_data; + AVDictionary *opts = NULL; + int len = strlen(p) * 6 / 8; + char *buf = av_mallocz(len); + av_base64_decode(buf, p, len); + + if (rtp_asf_fix_header(buf, len) < 0) + av_log(s, AV_LOG_ERROR, + "Failed to fix invalid RTSP-MS/ASF min_pktsize\n"); + init_packetizer(&pb, buf, len); + if (rt->asf_ctx) { + avformat_close_input(&rt->asf_ctx); + } + if (!(rt->asf_ctx = avformat_alloc_context())) + return AVERROR(ENOMEM); + rt->asf_ctx->pb = &pb; + av_dict_set(&opts, "no_resync_search", "1", 0); + ret = avformat_open_input(&rt->asf_ctx, "", &ff_asf_demuxer, &opts); + av_dict_free(&opts); + if (ret < 0) + return ret; + av_dict_copy(&s->metadata, rt->asf_ctx->metadata, 0); + rt->asf_pb_pos = avio_tell(&pb); + av_free(buf); + rt->asf_ctx->pb = NULL; + } + return ret; +} + +static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index, + PayloadContext *asf, const char *line) +{ + if (stream_index < 0) + return 0; + if (av_strstart(line, "stream:", &line)) { + RTSPState *rt = s->priv_data; + + s->streams[stream_index]->id = strtol(line, NULL, 10); + + if (rt->asf_ctx) { + int i; + + for (i = 0; i < rt->asf_ctx->nb_streams; i++) { + if (s->streams[stream_index]->id == rt->asf_ctx->streams[i]->id) { + *s->streams[stream_index]->codec = + *rt->asf_ctx->streams[i]->codec; + rt->asf_ctx->streams[i]->codec->extradata_size = 0; + rt->asf_ctx->streams[i]->codec->extradata = NULL; + avpriv_set_pts_info(s->streams[stream_index], 32, 1, 1000); + } + } + } + } + + return 0; +} + +struct PayloadContext { + AVIOContext *pktbuf, pb; + uint8_t *buf; +}; + +/** + * @return 0 when a packet was written into /p pkt, and no more data is left; + * 1 when a packet was written into /p pkt, and more packets might be left; + * <0 when not enough data was provided to return a full packet, or on error. + */ +static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf, + AVStream *st, AVPacket *pkt, + uint32_t *timestamp, + const uint8_t *buf, int len, uint16_t seq, + int flags) +{ + AVIOContext *pb = &asf->pb; + int res, mflags, len_off; + RTSPState *rt = s->priv_data; + + if (!rt->asf_ctx) + return -1; + + if (len > 0) { + int off, out_len = 0; + + if (len < 4) + return -1; + + av_freep(&asf->buf); + + ffio_init_context(pb, buf, len, 0, NULL, NULL, NULL, NULL); + + while (avio_tell(pb) + 4 < len) { + int start_off = avio_tell(pb); + + mflags = avio_r8(pb); + if (mflags & 0x80) + flags |= RTP_FLAG_KEY; + len_off = avio_rb24(pb); + if (mflags & 0x20) /**< relative timestamp */ + avio_skip(pb, 4); + if (mflags & 0x10) /**< has duration */ + avio_skip(pb, 4); + if (mflags & 0x8) /**< has location ID */ + avio_skip(pb, 4); + off = avio_tell(pb); + + if (!(mflags & 0x40)) { + /** + * If 0x40 is not set, the len_off field specifies an offset + * of this packet's payload data in the complete (reassembled) + * ASF packet. This is used to spread one ASF packet over + * multiple RTP packets. + */ + if (asf->pktbuf && len_off != avio_tell(asf->pktbuf)) { + uint8_t *p; + avio_close_dyn_buf(asf->pktbuf, &p); + asf->pktbuf = NULL; + av_free(p); + } + if (!len_off && !asf->pktbuf && + (res = avio_open_dyn_buf(&asf->pktbuf)) < 0) + return res; + if (!asf->pktbuf) + return AVERROR(EIO); + + avio_write(asf->pktbuf, buf + off, len - off); + avio_skip(pb, len - off); + if (!(flags & RTP_FLAG_MARKER)) + return -1; + out_len = avio_close_dyn_buf(asf->pktbuf, &asf->buf); + asf->pktbuf = NULL; + } else { + /** + * If 0x40 is set, the len_off field specifies the length of + * the next ASF packet that can be read from this payload + * data alone. This is commonly the same as the payload size, + * but could be less in case of packet splitting (i.e. + * multiple ASF packets in one RTP packet). + */ + + int cur_len = start_off + len_off - off; + int prev_len = out_len; + void *newmem; + out_len += cur_len; + if (FFMIN(cur_len, len - off) < 0) + return -1; + newmem = av_realloc(asf->buf, out_len); + if (!newmem) + return -1; + asf->buf = newmem; + memcpy(asf->buf + prev_len, buf + off, + FFMIN(cur_len, len - off)); + avio_skip(pb, cur_len); + } + } + + init_packetizer(pb, asf->buf, out_len); + pb->pos += rt->asf_pb_pos; + pb->eof_reached = 0; + rt->asf_ctx->pb = pb; + } + + for (;;) { + int i; + + res = ff_read_packet(rt->asf_ctx, pkt); + rt->asf_pb_pos = avio_tell(pb); + if (res != 0) + break; + for (i = 0; i < s->nb_streams; i++) { + if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id) { + pkt->stream_index = i; + return 1; // FIXME: return 0 if last packet + } + } + av_free_packet(pkt); + } + + return res == 1 ? -1 : res; +} + +static PayloadContext *asfrtp_new_context(void) +{ + return av_mallocz(sizeof(PayloadContext)); +} + +static void asfrtp_free_context(PayloadContext *asf) +{ + if (asf->pktbuf) { + uint8_t *p = NULL; + avio_close_dyn_buf(asf->pktbuf, &p); + asf->pktbuf = NULL; + av_free(p); + } + av_freep(&asf->buf); + av_free(asf); +} + +#define RTP_ASF_HANDLER(n, s, t) \ +RTPDynamicProtocolHandler ff_ms_rtp_ ## n ## _handler = { \ + .enc_name = s, \ + .codec_type = t, \ + .codec_id = AV_CODEC_ID_NONE, \ + .parse_sdp_a_line = asfrtp_parse_sdp_line, \ + .alloc = asfrtp_new_context, \ + .free = asfrtp_free_context, \ + .parse_packet = asfrtp_parse_packet, \ +} + +RTP_ASF_HANDLER(asf_pfv, "x-asf-pf", AVMEDIA_TYPE_VIDEO); +RTP_ASF_HANDLER(asf_pfa, "x-asf-pf", AVMEDIA_TYPE_AUDIO); |