/* * RTP parser for HEVC/H.265 payload format (draft version 6) * Copyright (c) 2014 Thomas Volkert * * 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/avstring.h" #include "avformat.h" #include "rtpdec.h" #define RTP_HEVC_PAYLOAD_HEADER_SIZE 2 #define RTP_HEVC_FU_HEADER_SIZE 1 #define RTP_HEVC_DONL_FIELD_SIZE 2 #define HEVC_SPECIFIED_NAL_UNIT_TYPES 48 /* SDP out-of-band signaling data */ struct PayloadContext { int using_donl_field; int profile_id; }; static const uint8_t start_sequence[] = { 0x00, 0x00, 0x00, 0x01 }; static av_cold PayloadContext *hevc_new_context(void) { return av_mallocz(sizeof(PayloadContext)); } static av_cold void hevc_free_context(PayloadContext *data) { av_free(data); } static av_cold int hevc_init(AVFormatContext *ctx, int st_index, PayloadContext *data) { av_dlog(ctx, "hevc_init() for stream %d\n", st_index); if (st_index < 0) return 0; ctx->streams[st_index]->need_parsing = AVSTREAM_PARSE_FULL; return 0; } static av_cold int hevc_sdp_parse_fmtp_config(AVFormatContext *s, AVStream *stream, PayloadContext *hevc_data, char *attr, char *value) { /* profile-space: 0-3 */ /* profile-id: 0-31 */ if (!strcmp(attr, "profile-id")) { hevc_data->profile_id = atoi(value); av_dlog(s, "SDP: found profile-id: %d\n", hevc_data->profile_id); } /* tier-flag: 0-1 */ /* level-id: 0-255 */ /* interop-constraints: [base16] */ /* profile-compatibility-indicator: [base16] */ /* sprop-sub-layer-id: 0-6, defines highest possible value for TID, default: 6 */ /* recv-sub-layer-id: 0-6 */ /* max-recv-level-id: 0-255 */ /* tx-mode: MSM,SSM */ /* sprop-vps: [base64] */ /* sprop-sps: [base64] */ /* sprop-pps: [base64] */ /* sprop-sei: [base64] */ /* max-lsr, max-lps, max-cpb, max-dpb, max-br, max-tr, max-tc */ /* max-fps */ /* sprop-max-don-diff: 0-32767 When the RTP stream depends on one or more other RTP streams (in this case tx-mode MUST be equal to "MSM" and MSM is in use), this parameter MUST be present and the value MUST be greater than 0. */ if (!strcmp(attr, "sprop-max-don-diff")) { if (atoi(value) > 0) hevc_data->using_donl_field = 1; av_dlog(s, "Found sprop-max-don-diff in SDP, DON field usage is: %d\n", hevc_data->using_donl_field); } /* sprop-depack-buf-nalus: 0-32767 */ if (!strcmp(attr, "sprop-depack-buf-nalus")) { if (atoi(value) > 0) hevc_data->using_donl_field = 1; av_dlog(s, "Found sprop-depack-buf-nalus in SDP, DON field usage is: %d\n", hevc_data->using_donl_field); } /* sprop-depack-buf-bytes: 0-4294967295 */ /* depack-buf-cap */ /* sprop-segmentation-id: 0-3 */ /* sprop-spatial-segmentation-idc: [base16] */ /* dec-parallel-ca: */ /* include-dph */ return 0; } static av_cold int hevc_parse_sdp_line(AVFormatContext *ctx, int st_index, PayloadContext *hevc_data, const char *line) { AVStream *current_stream; AVCodecContext *codec; const char *sdp_line_ptr = line; if (st_index < 0) return 0; current_stream = ctx->streams[st_index]; codec = current_stream->codec; if (av_strstart(sdp_line_ptr, "framesize:", &sdp_line_ptr)) { char str_video_width[50]; char *str_video_width_ptr = str_video_width; /* * parse "a=framesize:96 320-240" */ /* ignore spaces */ while (*sdp_line_ptr && *sdp_line_ptr == ' ') sdp_line_ptr++; /* ignore RTP payload ID */ while (*sdp_line_ptr && *sdp_line_ptr != ' ') sdp_line_ptr++; /* ignore spaces */ while (*sdp_line_ptr && *sdp_line_ptr == ' ') sdp_line_ptr++; /* extract the actual video resolution description */ while (*sdp_line_ptr && *sdp_line_ptr != '-' && (str_video_width_ptr - str_video_width) < sizeof(str_video_width) - 1) *str_video_width_ptr++ = *sdp_line_ptr++; /* add trailing zero byte */ *str_video_width_ptr = '\0'; /* determine the width value */ codec->width = atoi(str_video_width); /* jump beyond the "-" and determine the height value */ codec->height = atoi(sdp_line_ptr + 1); } else if (av_strstart(sdp_line_ptr, "fmtp:", &sdp_line_ptr)) { return ff_parse_fmtp(ctx, current_stream, hevc_data, sdp_line_ptr, hevc_sdp_parse_fmtp_config); } return 0; } static int hevc_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_hevc_ctx, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags) { const uint8_t *rtp_pl = buf; int tid, lid, nal_type; int first_fragment, last_fragment, fu_type; uint8_t new_nal_header[2]; int res = 0; /* sanity check for size of input packet: 1 byte payload at least */ if (len < RTP_HEVC_PAYLOAD_HEADER_SIZE + 1) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/HEVC packet, got %d bytes\n", len); return AVERROR_INVALIDDATA; } /* decode the HEVC payload header according to section 4 of draft version 6: 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |F| Type | LayerId | TID | +-------------+-----------------+ Forbidden zero (F): 1 bit NAL unit type (Type): 6 bits NUH layer ID (LayerId): 6 bits NUH temporal ID plus 1 (TID): 3 bits */ nal_type = (buf[0] >> 1) & 0x3f; lid = ((buf[0] << 5) & 0x20) | ((buf[1] >> 3) & 0x1f); tid = buf[1] & 0x07; /* sanity check for correct layer ID */ if (lid) { /* future scalable or 3D video coding extensions */ avpriv_report_missing_feature(ctx, "Multi-layer HEVC coding\n"); return AVERROR_PATCHWELCOME; } /* sanity check for correct temporal ID */ if (!tid) { av_log(ctx, AV_LOG_ERROR, "Illegal temporal ID in RTP/HEVC packet\n"); return AVERROR_INVALIDDATA; } /* sanity check for correct NAL unit type */ if (nal_type > 50) { av_log(ctx, AV_LOG_ERROR, "Unsupported (HEVC) NAL type (%d)\n", nal_type); return AVERROR_INVALIDDATA; } switch (nal_type) { /* aggregated packets (AP) */ case 48: /* pass the HEVC payload header */ buf += RTP_HEVC_PAYLOAD_HEADER_SIZE; len -= RTP_HEVC_PAYLOAD_HEADER_SIZE; /* pass the HEVC DONL field */ if (rtp_hevc_ctx->using_donl_field) { buf += RTP_HEVC_DONL_FIELD_SIZE; len -= RTP_HEVC_DONL_FIELD_SIZE; } /* fall-through */ /* video parameter set (VPS) */ case 32: /* sequence parameter set (SPS) */ case 33: /* picture parameter set (PPS) */ case 34: /* supplemental enhancement information (SEI) */ case 39: /* single NAL unit packet */ default: /* sanity check for size of input packet: 1 byte payload at least */ if (len < 1) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/HEVC packet, got %d bytes of NAL unit type %d\n", len, nal_type); return AVERROR_INVALIDDATA; } /* create A/V packet */ if ((res = av_new_packet(pkt, sizeof(start_sequence) + len)) < 0) return res; /* A/V packet: copy start sequence */ memcpy(pkt->data, start_sequence, sizeof(start_sequence)); /* A/V packet: copy NAL unit data */ memcpy(pkt->data + sizeof(start_sequence), buf, len); break; /* fragmentation unit (FU) */ case 49: /* pass the HEVC payload header */ buf += RTP_HEVC_PAYLOAD_HEADER_SIZE; len -= RTP_HEVC_PAYLOAD_HEADER_SIZE; if (len < 1) return AVERROR_INVALIDDATA; /* decode the FU header 0 1 2 3 4 5 6 7 +-+-+-+-+-+-+-+-+ |S|E| FuType | +---------------+ Start fragment (S): 1 bit End fragment (E): 1 bit FuType: 6 bits */ first_fragment = buf[0] & 0x80; last_fragment = buf[0] & 0x40; fu_type = buf[0] & 0x3f; /* pass the HEVC FU header */ buf += RTP_HEVC_FU_HEADER_SIZE; len -= RTP_HEVC_FU_HEADER_SIZE; /* pass the HEVC DONL field */ if (rtp_hevc_ctx->using_donl_field) { buf += RTP_HEVC_DONL_FIELD_SIZE; len -= RTP_HEVC_DONL_FIELD_SIZE; } av_dlog(ctx, " FU type %d with %d bytes\n", fu_type, len); if (len > 0) { new_nal_header[0] = (rtp_pl[0] & 0x81) | (fu_type << 1); new_nal_header[1] = rtp_pl[1]; /* start fragment vs. subsequent fragments */ if (first_fragment) { if (!last_fragment) { /* create A/V packet which is big enough */ if ((res = av_new_packet(pkt, sizeof(start_sequence) + sizeof(new_nal_header) + len)) < 0) return res; /* A/V packet: copy start sequence */ memcpy(pkt->data, start_sequence, sizeof(start_sequence)); /* A/V packet: copy new NAL header */ memcpy(pkt->data + sizeof(start_sequence), new_nal_header, sizeof(new_nal_header)); /* A/V packet: copy NAL unit data */ memcpy(pkt->data + sizeof(start_sequence) + sizeof(new_nal_header), buf, len); } else { av_log(ctx, AV_LOG_ERROR, "Illegal combination of S and E bit in RTP/HEVC packet\n"); res = AVERROR_INVALIDDATA; } } else { /* create A/V packet */ if ((res = av_new_packet(pkt, len)) < 0) return res; /* A/V packet: copy NAL unit data */ memcpy(pkt->data, buf, len); } } else { /* sanity check for size of input packet: 1 byte payload at least */ av_log(ctx, AV_LOG_ERROR, "Too short RTP/HEVC packet, got %d bytes of NAL unit type %d\n", len, nal_type); res = AVERROR_INVALIDDATA; } break; /* PACI packet */ case 50: /* Temporal scalability control information (TSCI) */ avpriv_report_missing_feature(ctx, "PACI packets for RTP/HEVC\n"); res = AVERROR_PATCHWELCOME; break; } pkt->stream_index = st->index; return res; } RTPDynamicProtocolHandler ff_hevc_dynamic_handler = { .enc_name = "HEVC", .codec_type = AVMEDIA_TYPE_VIDEO, .codec_id = AV_CODEC_ID_HEVC, .init = hevc_init, .parse_sdp_a_line = hevc_parse_sdp_line, .alloc = hevc_new_context, .free = hevc_free_context, .parse_packet = hevc_handle_packet }; RTPDynamicProtocolHandler ff_h265_dynamic_handler = { .enc_name = "H265", .codec_type = AVMEDIA_TYPE_VIDEO, .codec_id = AV_CODEC_ID_HEVC, .init = hevc_init, .parse_sdp_a_line = hevc_parse_sdp_line, .alloc = hevc_new_context, .free = hevc_free_context, .parse_packet = hevc_handle_packet };