android4.0 USB Camera Example (five auxiliary) JPG compression

Before the last one we said that a direct YUV into JPG that function but the conversion is not successful the main function is yuv420 to JPG based on research findings

The sequence of yuv420 is this

YYYY

YYYY

Uvuv

And the yuv422 sequence of interlaced scans is this

Yu yv yu yv yu yv

So make the following changes to the function such as

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, N, 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 + = +) {for (i = 0; i < +; 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); ELSECR[I/2] = input_image + width * ((i + j)/        2);    } jpeg_write_raw_data (&cinfo, data, 16);    } jpeg_finish_compress (&cinfo); Jpeg_destroy_compress (&Amp;cinfo);    memcpy (Dest_image,pbuf,jpglen); if (pbuf) free (PBUF); return Jpglen;}

You can convert the yuv422 directly into JPG.
interface function changes such as the following

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);}

Or is it quiet to study

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android4.0 USB Camera Example (five auxiliary) JPG compression