stm32f407驱动ov2640通过串口发送图像数据到上位机

醉迹满青山

问题：1.感觉图像采集速率不够快每秒2帧左右   请问 DCMI DMA这两个环节的传输速率是多少  是串口速率导致的整体速度慢吗
2.图像数据通过串口发送到上位机总报异常（上位机用Java写的）
javax.imageio.IIOException: Bogus marker length
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImageHeader(Native Method)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readNativeHeader(JPEGImageReader.java:620)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.checkTablesOnly(JPEGImageReader.java:347)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.gotoImage(JPEGImageReader.java:492)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readHeader(JPEGImageReader.java:613)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1070)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1050)
        at javax.imageio.ImageIO.read(ImageIO.java:1448)
        at javax.imageio.ImageIO.read(ImageIO.java:1352)
        at serialPort.DataView.exchangeImage(DataView.java:419)
        at serialPort.DataView$SerialListener.serialEvent(DataView.java:364)
        at gnu.io.RXTXPort.sendEvent(RXTXPort.java:772)
        at gnu.io.RXTXPort.eventLoop(Native Method)
        at gnu.io.RXTXPort$MonitorThread.run(RXTXPort.java:1641)
javax.imageio.IIOException: Huffman table 0x00 was not defined
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImage(Native Method)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1247)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1050)
        at javax.imageio.ImageIO.read(ImageIO.java:1448)
        at javax.imageio.ImageIO.read(ImageIO.java:1352)
        at serialPort.DataView.exchangeImage(DataView.java:419)
        at serialPort.DataView$SerialListener.serialEvent(DataView.java:364)
        at gnu.io.RXTXPort.sendEvent(RXTXPort.java:772)
        at gnu.io.RXTXPort.eventLoop(Native Method)
        at gnu.io.RXTXPort$MonitorThread.run(RXTXPort.java:1641)
javax.imageio.IIOException: Invalid JPEG file structure: two SOI markers
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImage(Native Method)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1247)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1050)
        at javax.imageio.ImageIO.read(ImageIO.java:1448)
        at javax.imageio.ImageIO.read(ImageIO.java:1352)
        at serialPort.DataView.exchangeImage(DataView.java:419)
        at serialPort.DataView$SerialListener.serialEvent(DataView.java:364)
        at gnu.io.RXTXPort.sendEvent(RXTXPort.java:772)
        at gnu.io.RXTXPort.eventLoop(Native Method)
        at gnu.io.RXTXPort$MonitorThread.run(RXTXPort.java:1641)
javax.imageio.IIOException: Huffman table 0x00 was not defined
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImage(Native Method)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1247)
        at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1050)
        at javax.imageio.ImageIO.read(ImageIO.java:1448)
        at javax.imageio.ImageIO.read(ImageIO.java:1352)
        at serialPort.DataView.exchangeImage(DataView.java:419)
        at serialPort.DataView$SerialListener.serialEvent(DataView.java:364)
        at gnu.io.RXTXPort.sendEvent(RXTXPort.java:772)
        at gnu.io.RXTXPort.eventLoop(Native Method)
        at gnu.io.RXTXPort$MonitorThread.run(RXTXPort.java:1641)

peng1554

记得原子这边是DCMI+dma传输JPEG数据，然后通过串口发送数据到上位机，可以增大串口波特率到921600看下

深沉的队长

想请问上位机是如何区分jpeg数据并转换的呢，看0xff和0xd8吗，那又怎么知道接收的图片的大小的呢？