前的最后一个　我们说，一个直接yuv变成jpg该功能　但是转换不成功　主要功能是yuv420转jpg的　根据研究发现

yuv420的序列是这种

YYYY

YYYY

UVUV

而yuv422的隔行扫描的序列是这种

YU YV YU YV YU YV

所以将函数作例如以下改动

static int put_jpeg_yuv420p_memory(unsigned char *dest_image,

                                   unsigned char *input_image, int width, int height)

{

    int i, j, jpeg_image_size;

    JSAMPROW y[16],cb[16],cr[16]; // y[2][5] = color sample of row 2 and pixel column 5; (one plane)

    JSAMPARRAY data[3]; // t[0][2][5] = color sample 0 of row 2 and column 5

    struct jpeg_compress_struct cinfo;

    struct jpeg_error_mgr jerr;

  	char *pbuf = NULL;

	int jpglen = 0;

    data[0] = y;

    data[1] = cb;

    data[2] = cr;

    cinfo.err = jpeg_std_error(&jerr);  // errors get written to stderr 

    jpeg_create_compress(&cinfo);

    cinfo.image_width = width;

    cinfo.image_height = height;

    cinfo.input_components = 3;

    jpeg_set_defaults (&cinfo);

    jpeg_set_colorspace(&cinfo, JCS_YCbCr);

    cinfo.raw_data_in = TRUE;                  // supply downsampled data

    cinfo.do_fancy_downsampling = FALSE;       // fix segfaulst with v7

    cinfo.comp_info[0].h_samp_factor = 2;

    cinfo.comp_info[0].v_samp_factor = 2;

    cinfo.comp_info[1].h_samp_factor = 1;

    cinfo.comp_info[1].v_samp_factor = 1;

    cinfo.comp_info[2].h_samp_factor = 1;

    cinfo.comp_info[2].v_samp_factor = 1;

    jpeg_set_quality(&cinfo, 80, TRUE);

    cinfo.dct_method = JDCT_FASTEST;

    jpeg_mem_dest(&cinfo, &pbuf, &jpglen);    // data written to mem

    jpeg_start_compress (&cinfo, TRUE);

    for (j = 0; j < height; j += 16) {

        for (i = 0; i < 16; i++) {

            y[i] = input_image + width * (i + j);

                //cb[i/2] = input_image + width * height + width / 2 * ((i + j) / 2);

                //cr[i/2] = input_image + width * height + width * height / 4 + width / 2 * ((i + j) / 2);

            if (i%2 == 0)

                cb[i/2] = input_image + width * ((i + j) / 2);

			else

				cr[i/2] = input_image + width * ((i + j) / 2);

        }

        jpeg_write_raw_data(&cinfo, data, 16);

    }

    jpeg_finish_compress(&cinfo);

    jpeg_destroy_compress(&cinfo);

    memcpy(dest_image,pbuf,jpglen);

	if(pbuf)

		free(pbuf);

    return jpglen;

}

就可以将yuv422直接转化成jpg

接口函数改动例如以下

JNIEXPORT jint JNICALL Java_com_hclydao_usbcamera_Fimcgzsd_writefile(JNIEnv * env, jclass obj,jbyteArray yuvdata,jbyteArray filename)//jintArray rgbdata

{

	jbyte *ydata = (jbyte*)(*env)->GetByteArrayElements(env, yuvdata, 0);

	jbyte *filedir = (jbyte*)(*env)->GetByteArrayElements(env, filename, 0);

	FILE * outfile;

  	if ((outfile = fopen(filedir, "wb")) == NULL) {

    	LOGE("++++++++++++open %s failed\n",filedir);

    	return -1;

  	}

	unsigned char* dst = malloc(mwidth*mheight*3*sizeof(char));

	int size = put_jpeg_yuv420p_memory(dst,ydata,mwidth,mheight);

	fwrite(dst,size,1,outfile);

	if(dst)free(dst);

	if(jpgdata)free(jpgdata);

	fclose(outfile);

	(*env)->ReleaseByteArrayElements(env, yuvdata, ydata, 0);

	(*env)->ReleaseByteArrayElements(env, filename, filedir, 0);

}

还是静下心来研究