tmcompress.c

可用于TM1300/PNX1300系列DSP（主要用于视频处理）压缩库即应用例子。

#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <zlib.h>
#include <sys/fcntlcom.h>
#include <unistd.h>

static const char *progname = NULL;

static unsigned long total_in = 0;
static unsigned long total_out = 0;

static const int True = 1;
static const int False = 0;


/*************************************************************************
Compression algorithm
**************************************************************************/

int do_compress(int fi, int fo)
{
   
   uLong in_len;
   uLongf out_len;
   int lv_ret = 0;
   
   void *inmem = NULL;
   void *outmem = NULL;

   struct stat st;
   int    total_size;

   /* get size of input file */
   if (fstat(fi,&st) == -1 )
   {
      printf("%s: fstat error with input file\n", progname);
      close(fi);
      exit(1);
   }
   
   /* save total size */
   total_size    = st.st_size;

   /* allocate memory buffers */
   inmem = malloc(total_size);
   outmem = malloc(total_size + ((total_size*0.015)+1) +12 );

   /* if memory allocation failed */
   if (inmem == NULL || outmem == NULL)
   {
      printf("%s: out of memory\n", progname);
      lv_ret = 1;
      goto err;
   }
   
   /* fill in max output/input length */
   in_len = total_size;
   out_len = total_size + ((total_size*0.015)+1) +12;
      
   /* write compressed block */
   if ((lv_ret = read(fi,inmem,in_len)) != in_len)
   {
      printf("\nread error  (disk error ?) %d %d\n",lv_ret, in_len);
      goto err;
   }


   /* compress block */
   lv_ret = compress(outmem,&out_len,inmem,in_len);
   if (lv_ret != Z_OK)
   {
      /* this should NEVER happen */
      printf("internal error - compression failed: %d, outlen %d, inlen %d\n",
            lv_ret,out_len,in_len);
      lv_ret = 2;
      goto err;
   }

   /* write compressed block */
   if ((lv_ret = write(fo,outmem,out_len)) != out_len)
   {
      printf("\nwrite error  (disk full ?) %d %d\n",lv_ret, out_len);
      goto err;
   }

   /* no error */
   total_out = out_len;
   total_in = in_len;

   lv_ret = 0;

err:
   free(outmem);
   free(inmem);
   return lv_ret;
}



/*************************************************************************
//
**************************************************************************/

int main(int argc, char *argv[])
{
	int i = 1;
	int ret = 0;
	int fi = 0;
	int fo = 0;
	const char *in_name = NULL;
	const char *out_name = NULL;


	progname = argv[0];

        /* if three arguements were not input */
	if (3 != argc)
	{
		printf("usage: %s input-file output-file\n", progname);
		exit(1);
	}

        /* get input file name */
 	in_name = argv[i++];

        /* open the input files */
        fi = open(in_name,O_RDONLY);
	if (fi == -1)
	{
		printf("%s: cannot open input file %s\n", progname, in_name);
		exit(1);
	}

        /* get output file name */
        out_name = argv[i++];

         /* open/create output file */
         fo = open(out_name,O_WRONLY|O_CREAT);
         if (fo == -1)
         {
            printf("%s: cannot create output file %s\n", progname, out_name);
            close(fi);
            exit(1);
         }

         /* compress file */
        ret = do_compress(fi,fo);
        if (ret == 0)
           printf("%14s, compression  %2.2f, before %6ld bytes, after %6ld bytes\n",in_name,(total_out*100.0)/total_in, total_in, total_out);

        /* close all files */
	close(fi);
	if (fo) close(fo);

        /* make the output file read/writeable/executable  */
        chmod(out_name,0x1FF);

      /* exit */
	return ret;
}