docs: enhance README with detailed explanation of SIP and SDP architecture

note: the `API.md` said it's `zoom_in` and `zoom_out` with underscore, while the go ptzCmdMap said it's `zoomin` and `zoomout` with underscore; I choose to support both (or unify them?)

.gitignore

@@ -23,3 +23,5 @@
 hs_err_pid*
 objs
 .idea
+
+run

Dockerfile

@@ -1,16 +1,29 @@
 # 引入SRS
-FROM ossrs/srs:v6.0.155 AS srs
+FROM ossrs/srs:v6.0.184 AS srs
 
 # 前端构建阶段
 FROM node:20-slim AS frontend-builder
+ARG HTTP_PROXY=
+ARG NO_PROXY=
+ENV http_proxy=${HTTP_PROXY} \
+    https_proxy=${HTTP_PROXY} \
+    no_proxy=${NO_PROXY}
 WORKDIR /app/frontend
 COPY html/NextGB/package*.json ./
+# RUN npm config set registry http://mirrors.cloud.tencent.com/npm/ \
+#     && npm install
 RUN npm install 
 COPY html/NextGB/ .
 RUN npm run build
 
 # 后端构建阶段
 FROM golang:1.23 AS backend-builder
+ARG HTTP_PROXY=
+ARG NO_PROXY=
+ENV http_proxy=${HTTP_PROXY} \
+    https_proxy=${HTTP_PROXY} \
+    no_proxy=${NO_PROXY} \
+    GOPROXY=https://goproxy.cn,direct
 WORKDIR /app
 COPY go.mod go.sum ./
 RUN go mod download
@@ -19,11 +32,20 @@ RUN CGO_ENABLED=0 GOOS=linux go build -o /app/srs-sip main/main.go
 
 # 最终运行阶段
 FROM ubuntu:22.04
+ARG HTTP_PROXY=
+ARG NO_PROXY=
+ENV http_proxy=${HTTP_PROXY} \
+    https_proxy=${HTTP_PROXY} \
+    no_proxy=${NO_PROXY}
 WORKDIR /usr/local
 
 # 设置时区
 ENV TZ=Asia/Shanghai
-RUN apt-get update && \
+RUN sed -i \
+    -e 's@http://archive.ubuntu.com/ubuntu/@http://mirrors.ustc.edu.cn/ubuntu/@g' \
+    -e 's@http://security.ubuntu.com/ubuntu/@http://mirrors.ustc.edu.cn/ubuntu/@g' \
+    /etc/apt/sources.list && \
+    apt-get update && \
     apt-get install -y ca-certificates tzdata supervisor && \
     ln -fs /usr/share/zoneinfo/$TZ /etc/localtime && \
     dpkg-reconfigure -f noninteractive tzdata && \
@@ -60,7 +82,7 @@ stderr_logfile=/dev/stderr\n\
 stderr_logfile_maxbytes=0\n\
 \n\
 [program:srs-sip]\n\
-command=/usr/local/srs-sip/srs-sip\n\
+command=/usr/local/srs-sip/srs-sip -c /usr/local/srs-sip/config.yaml\n\
 directory=/usr/local/srs-sip\n\
 autostart=true\n\
 autorestart=true\n\

README_cross.md

@@ -0,0 +1,78 @@
+# note to me
+
+```bash
+docker compose build --network host
+```
+
+```
+docker compose up -d --force-recreate
+```
+
+# TODO
+
+- [ ] let user choose whether use mirror (use which mirror) when building Dockerfile 
+
+---
+
+Based on the logs and the **GB/T 28181-2022** standard you provided, here is the explanation:
+
+Yes, this is **SIP**, but the content *inside* the SIP message is **SDP (Session Description Protocol)**.
+
+While XML is used for *control* (like PTZ), **SDP** is used for **Media Negotiation** (setting up the video stream).
+
+### The Architecture from your logs
+1.  **SIP (The Envelope):** Starts the conversation ("I want to watch video").
+2.  **SDP (The Letter inside):** Describes technical details ("Send video to IP X, Port Y, using Format Z").
+3.  **RTP (The result):** After this SIP/SDP handshake finishes, the actual binary video stream (PS/H.264) starts flowing over a separate TCP/UDP connection.
+
+### Breakdown of your Log
+This log shows a **Real-time Live View** handshake.
+
+#### 1. The Request (SRS Server -> Camera)
+The Server asks the Camera to send video.
+
+```ini
+INVITE sip:34020000001320000001@3402000000 SIP/2.0
+Content-Type: application/sdp
+
+s=Play                         # "Play" = Real-time Live View (Standard 9.2.2.1)
+c=IN IP4 192.168.2.184         # The Media Server IP
+m=video 9000 TCP/RTP/AVP 96    # "Send video to my Port 9000 via TCP"
+a=recvonly                     # "I will only receive, not send"
+y=0911024252                   # **GB/T 28181 Special**: The SSRC (Stream ID)
+```
+
+#### 2. The Response (Camera -> SRS Server)
+The Camera agrees and tells the server its own details.
+
+```ini
+SIP/2.0 200 OK
+Content-Type: application/sdp
+
+c=IN IP4 192.168.2.64          # The Camera IP
+m=video 15060 TCP/RTP/AVP 96   # "I am sending from Port 15060"
+a=sendonly                     # "I will only send"
+a=setup:active                 # "I will initiate the TCP connection to you"
+y=0911024252                   # Matches the SSRC provided
+f=v/2/2560x1440/25/2/8192a/... # **GB/T 28181 Special**: Media Info
+```
+
+### Key Differences from Standard SDP
+GB/T 28181 modifies standard SDP with two specific fields mandatory for this protocol:
+
+1.  **`y=` (SSRC)**:
+    *   **Standard SDP:** Does not have a `y` line.
+    *   **GB/T 28181:** Uses `y` to define the **SSRC** (Synchronization Source). This 10-digit number is crucial because it marks every binary video packet sent later. If the binary stream headers don't match this `y` value, the stream is rejected.
+
+2.  **`f=` (Media Info)**:
+    *   **Standard SDP:** Does not have an `f` line.
+    *   **GB/T 28181:** Uses `f` to describe video parameters. In your log: `v/2/2560x1440/25...` means:
+        *   `v`: Video
+        *   `2`: Coding format (likely H.264 or H.265 mapped)
+        *   `2560x1440`: Resolution
+        *   `25`: Frame rate
+
+### Summary of Cooperation
+1.  **XML (SIP MESSAGE):** Used for "remote control" (PTZ, Query, Keepalive).
+2.  **SDP (SIP INVITE):** Used to *negotiate* the pipeline.
+3.  **Binary (RTP/PS):** The actual heavy video data that flows through the pipe created by the SDP.

conf/srs.conf

@@ -3,6 +3,11 @@ max_connections     1000;
 # For docker, please use docker logs to manage the logs of SRS.
 # See https://docs.docker.com/config/containers/logging/
 srs_log_tank        console;
+
+# srs_log_tank        file;
+# srs_log_file        /var/log/srs/srs.log;
+# ff_log_dir          /var/log/srs;
+
 daemon              off;
 disable_daemon_for_docker off;
 http_api {

doc/API.md

@@ -277,8 +277,8 @@ SRS-SIP 是一个基于 GB28181 协议的视频监控系统，提供设备管理
   - `down`: 向下
   - `left`: 向左
   - `right`: 向右
-  - `zoom_in`: 放大
-  - `zoom_out`: 缩小
+  - `zoomin`: 放大
+  - `zoomout`: 缩小
   - `stop`: 停止
 - `speed`: 控制速度（1-9）
 

docker-compose.yml

@@ -0,0 +1,33 @@
+services:
+  srs-sip:
+    build:
+      context: .
+      network: host
+      args:
+        HTTP_PROXY: ${HTTP_PROXY:-}
+        NO_PROXY: "localhost,127.0.0.1,::1"
+    environment:
+      # CANDIDATE: ${CANDIDATE:-}
+      CANDIDATE: 192.168.2.184
+      TZ: "Asia/Shanghai"
+    volumes:
+      - ./run/conf/config.yaml:/usr/local/srs-sip/config.yaml:ro
+      - ./run/logs:/usr/local/srs-sip/logs
+      - ./run/srs/conf/srs.conf:/usr/local/srs/conf/srs.conf:ro
+      # use docker logs
+      - ./run/srs/logs:/var/log/srs/
+      # for recording
+      - ./run/data:/data
+    ports:
+      # SRS RTMP
+      - "1985:1985"
+      # SRS media ingest (GB28181 RTP/PS 等，取决于你的配置)
+      - "9000:9000"
+      # SRS WebRTC
+      - "8000:8000/udp"
+      # SIP
+      - "5060:5060"
+      - "5060:5060/udp"
+      # WebUI
+      - "8025:8025"
+    restart: unless-stopped

html/NextGB/src/views/realplay/PtzControlPanel.vue

@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import { ref, computed } from 'vue'
-import { ArrowRight, VideoCamera } from '@element-plus/icons-vue'
+import { ArrowRight, VideoCamera, ZoomIn, ZoomOut } from '@element-plus/icons-vue'
 import {
   ArrowUp,
   ArrowDown,
@@ -158,6 +158,27 @@ const isDisabled = computed(() => !props.activeWindow)
               <div class="direction-center"></div>
             </div>
           </div>
+          <div class="zoom-controls">
+            <el-button
+              class="zoom-btn"
+              :disabled="isDisabled"
+              @mousedown="handlePtzStart('zoomin')"
+              @mouseup="handlePtzStop"
+              @mouseleave="handlePtzStop"
+            >
+              <el-icon><ZoomIn /></el-icon>
+            </el-button>
+            <div class="zoom-label">变倍</div>
+            <el-button
+              class="zoom-btn"
+              :disabled="isDisabled"
+              @mousedown="handlePtzStart('zoomout')"
+              @mouseup="handlePtzStop"
+              @mouseleave="handlePtzStop"
+            >
+              <el-icon><ZoomOut /></el-icon>
+            </el-button>
+          </div>
           <div class="speed-control">
             <div class="speed-value">{{ speed }}</div>
             <el-slider
@@ -346,6 +367,48 @@ const isDisabled = computed(() => !props.activeWindow)
   border-radius: 4px;
 }
 
+.zoom-controls {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 6px;
+  height: 120px;
+  justify-content: center;
+}
+
+.zoom-btn {
+  --el-button-bg-color: var(--el-color-primary-light-8);
+  --el-button-border-color: var(--el-color-primary-light-5);
+  --el-button-hover-bg-color: var(--el-color-primary-light-7);
+  --el-button-hover-border-color: var(--el-color-primary-light-4);
+  --el-button-active-bg-color: var(--el-color-primary-light-5);
+  --el-button-active-border-color: var(--el-color-primary);
+
+  width: 36px;
+  height: 36px;
+  padding: 0;
+  margin: 0;
+  border-radius: 4px;
+  
+  .el-icon {
+    font-size: 18px;
+  }
+
+  &:hover {
+    transform: scale(1.05);
+  }
+
+  &:active {
+    transform: scale(0.95);
+  }
+}
+
+.zoom-label {
+  font-size: 12px;
+  color: var(--el-text-color-secondary);
+  font-weight: 500;
+}
+
 .control-groups,
 .control-group {
   display: none;