APP_Framework/Applications/:add TJpgDec example,notes the macro definition (WORK_POOL_SIZE),this value depends on the resolution of the image,user set.

APP_Framework/Applications/knowing_app/image_processing/TJpgDec_APP/tjpgd_example.c

@@ -0,0 +1,151 @@
+#include <transform.h>
+#include <tjpgd.h>
+#define WORK_POOL_SIZE (4*1024+32)//This value depends on the resolution of the image
+
+/* User defined device identifier */
+typedef struct {
+    FILE *fp;          /* File pointer for input function */
+    uint8_t *fbuf;     /* Pointer to the frame buffer for output function */
+    uint16_t wfbuf;    /* Width of the frame buffer [pix] */
+} IODEV;
+
+
+/*------------------------------*/
+/* User defined input funciton  */
+/*------------------------------*/
+
+unsigned int in_func (JDEC* jd, uint8_t* buff, unsigned int nbyte)
+{
+    IODEV *dev = (IODEV*)jd->device;   /* Device identifier for the session (5th argument of jd_prepare function) */
+
+
+    if (buff) {
+        /* Read bytes from input stream */
+        return (uint16_t)fread(buff, 1, nbyte, dev->fp);
+    } else {
+        /* Remove bytes from input stream */
+        return fseek(dev->fp, nbyte, SEEK_CUR) ? 0 : nbyte;
+    }
+}
+
+
+/*------------------------------*/
+/* User defined output funciton */
+/*------------------------------*/
+
+int out_func (JDEC* jd, void* bitmap, JRECT* rect)
+{
+    IODEV *dev = (IODEV*)jd->device;
+    uint8_t *src, *dst;
+    uint16_t y, bws, bwd;
+
+
+    /* Put progress indicator */
+    if (rect->left == 0) {
+        printf("\r%lu%%", (rect->top << jd->scale) * 100UL / jd->height);
+    }
+
+    /* Copy the decompressed RGB rectanglar to the frame buffer (assuming RGB888 cfg) */
+    src = (uint8_t*)bitmap;
+    dst = dev->fbuf + 3 * (rect->top * dev->wfbuf + rect->left);  /* Left-top of destination rectangular */
+    bws = 3 * (rect->right - rect->left + 1);     /* Width of source rectangular [byte] */
+    bwd = 3 * dev->wfbuf;                         /* Width of frame buffer [byte] */
+    for (y = rect->top; y <= rect->bottom; y++) {
+        memcpy(dst, src, bws);   /* Copy a line */
+        src += bws; dst += bwd;  /* Next line */
+    }
+
+    return 1;    /* Continue to decompress */
+}
+
+
+/*------------------------------*/
+/* Program Jpeg_Dec             */
+/*------------------------------*/
+
+int Jpeg_Dec (int argc, char* argv[])
+{
+    void *work;       /* Pointer to the decompressor work area */
+    JDEC jdec;        /* Decompression object */
+    JRESULT res;      /* Result code of TJpgDec API */
+    IODEV devid;      /* User defined device identifier */
+
+    /* Open a JPEG file */
+    if (argc < 2)
+    {
+        printf("Jpeg_Dec illegal arguments ...\n");
+        return -1;
+    }
+
+    devid.fp = fopen(argv[1], "r+");
+    if (!devid.fp)
+    {
+        printf("Jpeg_Dec open the file failed...\n");
+        return -1;
+    }
+
+    /* Allocate a work area for TJpgDec */
+    work = malloc(WORK_POOL_SIZE);
+    if(work == NULL)
+    {
+        printf("Jpeg_Dec work malloc failed...\n");
+        res = -1;
+        goto __exit;
+    }
+
+    /* Prepare to decompress */
+    res = jd_prepare(&jdec, in_func, work, WORK_POOL_SIZE, &devid);
+    if (res == JDR_OK)
+    {
+        /* Ready to dcompress. Image info is available here. */
+        printf("Image dimensions: %u by %u. %u bytes used.\n", jdec.width, jdec.height, 3100 - jdec.sz_pool);
+
+        devid.fbuf = malloc(3 * jdec.width * jdec.height); /* Frame buffer for output image (assuming RGB888 cfg) */
+        if(devid.fbuf == RT_NULL)
+        {
+            printf("Jpeg_Dec devid.fbuf malloc failed, need to use %d Bytes ...\n", 3 * jdec.width * jdec.height);
+            res = -1;
+            goto __exit;
+        }
+        devid.wfbuf = jdec.width;
+
+        res = jd_decomp(&jdec, out_func, 0);   /* Start to decompress with 1/1 scaling */
+        if (res == JDR_OK) {
+            /* Decompression succeeded. You have the decompressed image in the frame buffer here. */
+            printf("\rOK  \n");
+            // for(int j = 0; j<3 * jdec.width * jdec.height;j++)
+            // {
+            //     printf("%d,",*(devid.fbuf+j));
+            // }
+            
+        }
+        else
+        {
+            printf("Failed to decompress: rc=%d\n", res);
+        }
+
+        if(devid.fbuf != NULL)
+        {
+            free(devid.fbuf);    /* Discard frame buffer */
+        }
+
+    }
+    else
+    {
+        printf("Failed to prepare: rc=%d\n", res);
+    }
+
+__exit:
+    if(work != NULL)
+    {
+        free(work);             /* Discard work area */
+    }
+
+    fclose(devid.fp);       /* Close the JPEG file */
+
+    return res;
+}
+#ifdef __RT_THREAD_H__
+MSH_CMD_EXPORT(Jpeg_Dec, Jpeg Decode Test);
+#endif
+