diff --git a/av/codec/hevc/const.go b/av/codec/hevc/const.go index 0ef608f..31c0935 100755 --- a/av/codec/hevc/const.go +++ b/av/codec/hevc/const.go @@ -75,6 +75,7 @@ const ( NalUnspec63 = 63 // RTP 中扩展 + NalStapInRtp = 48 NalFuInRtp = 49 ) diff --git a/av/format/rtp/h265_depacketizer.go b/av/format/rtp/h265_depacketizer.go new file mode 100644 index 0000000..3bdb686 --- /dev/null +++ b/av/format/rtp/h265_depacketizer.go @@ -0,0 +1,194 @@ +// Copyright (c) 2019,CAOHONGJU All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package rtp + +import ( + "github.com/cnotch/ipchub/av/codec" + "github.com/cnotch/ipchub/av/codec/hevc" +) + +type h265Depacketizer struct { + fragments []*Packet // 分片包 + video *codec.VideoMeta + w codec.FrameWriter + syncClock SyncClock +} + +// NewH265Depacketizer 实例化 H265 帧提取器 +func NewH265Depacketizer(video *codec.VideoMeta, w codec.FrameWriter) Depacketizer { + fe := &h265Depacketizer{ + video: video, + fragments: make([]*Packet, 0, 16), + w: w, + } + fe.syncClock.RTPTimeUnit = 1000.0 / float64(video.ClockRate) + return fe +} + +func (h265dp *h265Depacketizer) Control(p *Packet) error { + h265dp.syncClock.Decode(p.Data) + return nil +} + +/* + * 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 + * 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 + */ +func (h265dp *h265Depacketizer) Depacketize(packet *Packet) (err error) { + if h265dp.syncClock.NTPTime == 0 { // 未收到同步时钟信息，忽略任意包 + return + } + + payload := packet.Payload() + if len(payload) < 3 { + return + } + + naluType := (payload[0] >> 1) & 0x3f + + switch naluType { + case hevc.NalStapInRtp: // 在RTP中的聚合（AP） + return h265dp.depacketizeStap(packet) + case hevc.NalFuInRtp: // 在RTP中的扩展,分片(FU) + return h265dp.depacketizeFu(packet) + default: + frame := &codec.Frame{ + MediaType: codec.MediaTypeVideo, + AbsTimestamp: h265dp.rtp2ntp(packet.Timestamp), + Payload: payload, + } + err = h265dp.writeFrame(frame) + return + } +} + +func (h265dp *h265Depacketizer) depacketizeStap(packet *Packet) (err error) { + payload := packet.Payload() + off := 2 // 跳过 STAP NAL HDR + + // 循环读取被封装的NAL + for { + // nal长度 + nalSize := ((uint16(payload[off])) << 8) | uint16(payload[off+1]) + if nalSize < 1 { + return + } + + off += 2 + frame := &codec.Frame{ + MediaType: codec.MediaTypeVideo, + AbsTimestamp: h265dp.rtp2ntp(packet.Timestamp), + Payload: make([]byte, nalSize), + } + copy(frame.Payload, payload[off:]) + if err = h265dp.writeFrame(frame); err != nil { + return + } + off += int(nalSize) + if off >= len(payload) { // 扫描完成 + break + } + } + return +} + +func (h265dp *h265Depacketizer) depacketizeFu(packet *Packet) (err error) { + payload := packet.Payload() + rawDataOffset := 3 // 原始数据的偏移 = FU indicator + header + + // 0 1 2 3 4 5 6 7 + // +-+-+-+-+-+-+-+-+ + // |S|E| FuType | + // +---------------+ + fuHeader := payload[2] + + if (fuHeader>>7)&1 == 1 { // 第一个分片包 + h265dp.fragments = h265dp.fragments[:0] + // 缓存片段 + h265dp.fragments = append(h265dp.fragments, packet) + return + } + + if len(h265dp.fragments) == 0 || (len(h265dp.fragments) != 0 && + h265dp.fragments[len(h265dp.fragments)-1].SequenceNumber != packet.SequenceNumber-1) { + // Packet loss ? + h265dp.fragments = h265dp.fragments[:0] + return + } + + // 缓存其他片段 + h265dp.fragments = append(h265dp.fragments, packet) + + if (fuHeader>>6)&1 == 1 { // 最后一个片段 + frameLen := 2 // 计算帧总长,初始 naluType header len + for _, fragment := range h265dp.fragments { + frameLen += len(fragment.Payload()) - rawDataOffset + } + + frame := &codec.Frame{ + MediaType: codec.MediaTypeVideo, + AbsTimestamp: h265dp.rtp2ntp(packet.Timestamp), + Payload: make([]byte, frameLen), + } + + frame.Payload[0] = (payload[0] & 0x81) | (fuHeader&0x3f)<<1 + frame.Payload[1] = payload[1] + offset := 2 + for _, fragment := range h265dp.fragments { + payload := fragment.Payload()[rawDataOffset:] + copy(frame.Payload[offset:], payload) + offset += len(payload) + } + // 清空分片缓存 + h265dp.fragments = h265dp.fragments[:0] + + err = h265dp.writeFrame(frame) + } + + return +} + +func (h265dp *h265Depacketizer) rtp2ntp(timestamp uint32) int64 { + return h265dp.syncClock.Rtp2Ntp(timestamp) +} + +func (h265dp *h265Depacketizer) writeFrame(frame *codec.Frame) error { + nalType := (frame.Payload[0] >> 1) & 0x3f + switch nalType { + case hevc.NalVps: + if len(h265dp.video.Vps) == 0 { + h265dp.video.Vps = frame.Payload + } + case hevc.NalSps: + if len(h265dp.video.Sps) == 0 { + h265dp.video.Sps = frame.Payload + } + case hevc.NalPps: + if len(h265dp.video.Pps) == 0 { + h265dp.video.Pps = frame.Payload + } + } + return h265dp.w.WriteFrame(frame) +} diff --git a/media/cache/hevccache.go b/media/cache/hevccache.go index 90c6104..01eee25 100755 --- a/media/cache/hevccache.go +++ b/media/cache/hevccache.go @@ -117,33 +117,39 @@ func (cache *HevcCache) getPalyloadType(payload []byte) (vps, sps, pps, islice b if len(payload) < 3 { return } - - // +---------------+---------------+ - // |0|1|2|3|4|5|6|7|0|1|2|3|4|5|6|7| - // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - // |F| Type | LayerId | TID | - // +-------------+-----------------+ naluType := (payload[0] >> 1) & 0x3f - // 在RTP中的扩展,分片(FU) - if naluType == hevc.NalFuInRtp { - // 0 1 2 3 4 5 6 7 - // +-+-+-+-+-+-+-+-+ - // |S|E| FuType | - // +---------------+ + switch naluType { + case hevc.NalStapInRtp: // 在RTP中的聚合（AP） + off := 2 + // 循环读取被封装的NAL + for { + // nal长度 + nalSize := ((uint16(payload[off])) << 8) | uint16(payload[off+1]) + if nalSize < 1 { + return + } + + off += 2 + naluType = (payload[off] >> 1) & 0x3f + cache.nalType(naluType, &vps, &sps, &pps, &islice) + off += int(nalSize) + + if off >= len(payload) { // 扫描完成 + break + } + } + return + case hevc.NalFuInRtp: // 在RTP中的扩展,分片(FU) naluType = payload[2] & 0x3f if (payload[2]>>7)&1 == 1 { // 第一个分片 cache.nalType(naluType, &vps, &sps, &pps, &islice) } return - } - - // 如果是原生的 HEVC NAL - if naluType <= hevc.NalRsvNvcl47 { + default: cache.nalType(naluType, &vps, &sps, &pps, &islice) return } - return } func (cache *HevcCache) nalType(nalType byte, vps, sps, pps, islice *bool) {