More options for Zopfli binary

9 files changed, 108 insertions, 53 deletions

diff --git a/deflate.c b/deflate.c
index 1ce25bb..713c6ae 100644
--- a/deflate.c
+++ b/deflate.c
@@ -689,4 +689,10 @@ void ZopfliDeflate(const ZopfliOptions* options, int btype, int final,
     i += size;
   }
 #endif
+  if (options->verbose) {
+    fprintf(stderr,
+            "Original Size: %d, Deflate: %d, Compression: %f%% Removed\n",
+            (int)insize, (int)*outsize,
+            100.0 * (double)(insize - *outsize) / (double)insize);
+  }
 }
diff --git a/gzip_container.c b/gzip_container.c
index b68667f..8a062f2 100644
--- a/gzip_container.c
+++ b/gzip_container.c
@@ -110,8 +110,8 @@ void ZopfliGzipCompress(const ZopfliOptions* options,
 
   if (options->verbose) {
     fprintf(stderr,
-            "Original Size: %d, Compressed: %d, Compression: %f%% Removed\n",
+            "Original Size: %d, Gzip: %d, Compression: %f%% Removed\n",
             (int)insize, (int)*outsize,
-            100.0f * (float)(insize - *outsize) / (float)insize);
+            100.0 * (double)(insize - *outsize) / (double)insize);
   }
 }
diff --git a/lz77.c b/lz77.c
index a9dc4d3..26186b4 100644
--- a/lz77.c
+++ b/lz77.c
@@ -64,16 +64,30 @@ void ZopfliStoreLitLenDist(unsigned short length, unsigned short dist,
 }
 
 /*
-Gets the value of the length given the distance. Typically, the value of the
-length is the length, but if the distance is very long, decrease the value of
-the length a bit to make up for the fact that long distances use large amounts
-of extra bits.
+Gets a score of the length given the distance. Typically, the score of the
+length is the length itself, but if the distance is very long, decrease the
+score of the length a bit to make up for the fact that long distances use large
+amounts of extra bits.
+
+This is not an accurate score, it is a heuristic only for the greedy LZ77
+implementation. More accurate cost models are employed later. Making this
+heuristic more accurate may hurt rather than improve compression.
+
+The two direct uses of this heuristic are:
+-avoid using a length of 3 in combination with a long distance. This only has
+ an effect if length == 3.
+-make a slightly better choice between the two options of the lazy matching.
+
+Indirectly, this affects:
+-the block split points if the default of block splitting first is used, in a
+ rather unpredictable way
+-the first zopfli run, so it affects the chance of the first run being closer
+ to the optimal output
 */
-static int GetLengthValue(int length, int distance) {
+static int GetLengthScore(int length, int distance) {
   /*
-  At distance > 1024, using length 3 is no longer good, due to the large amount
-  of extra bits for the distance code. distance > 1024 uses 9+ extra bits, and
-  this seems to be the sweet spot.
+  At 1024, the distance uses 9+ extra bits and this seems to be the sweet spot
+  on tested files.
   */
   return distance > 1024 ? length - 1 : length;
 }
@@ -355,7 +369,7 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
   size_t i = 0, j;
   unsigned short leng;
   unsigned short dist;
-  int lengvalue;
+  int lengthscore;
   size_t windowstart = instart > ZOPFLI_WINDOW_SIZE
       ? instart - ZOPFLI_WINDOW_SIZE : 0;
   unsigned short dummysublen[259];
@@ -367,7 +381,7 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
   /* Lazy matching. */
   unsigned prev_length = 0;
   unsigned prev_match = 0;
-  int prevlengvalue;
+  int prevlengthscore;
   int match_available = 0;
 #endif
 
@@ -384,16 +398,16 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
 
     ZopfliFindLongestMatch(s, h, in, i, inend, ZOPFLI_MAX_MATCH, dummysublen,
                            &dist, &leng);
-    lengvalue = GetLengthValue(leng, dist);
+    lengthscore = GetLengthScore(leng, dist);
 
 #ifdef ZOPFLI_LAZY_MATCHING
     /* Lazy matching. */
-    prevlengvalue = GetLengthValue(prev_length, prev_match);
+    prevlengthscore = GetLengthScore(prev_length, prev_match);
     if (match_available) {
       match_available = 0;
-      if (lengvalue > prevlengvalue + 1) {
+      if (lengthscore > prevlengthscore + 1) {
         ZopfliStoreLitLenDist(in[i - 1], 0, store);
-        if (lengvalue >= ZOPFLI_MIN_MATCH && lengvalue < ZOPFLI_MAX_MATCH) {
+        if (lengthscore >= ZOPFLI_MIN_MATCH && leng < ZOPFLI_MAX_MATCH) {
           match_available = 1;
           prev_length = leng;
           prev_match = dist;
@@ -403,7 +417,7 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
         /* Add previous to output. */
         leng = prev_length;
         dist = prev_match;
-        lengvalue = prevlengvalue;
+        lengthscore = prevlengthscore;
         /* Add to output. */
         ZopfliVerifyLenDist(in, inend, i - 1, dist, leng);
         ZopfliStoreLitLenDist(leng, dist, store);
@@ -415,7 +429,7 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
         continue;
       }
     }
-    else if (lengvalue >= ZOPFLI_MIN_MATCH && leng < ZOPFLI_MAX_MATCH) {
+    else if (lengthscore >= ZOPFLI_MIN_MATCH && leng < ZOPFLI_MAX_MATCH) {
       match_available = 1;
       prev_length = leng;
       prev_match = dist;
@@ -425,7 +439,7 @@ void ZopfliLZ77Greedy(ZopfliBlockState* s, const unsigned char* in,
 #endif
 
     /* Add to output. */
-    if (lengvalue >= ZOPFLI_MIN_MATCH) {
+    if (lengthscore >= ZOPFLI_MIN_MATCH) {
       ZopfliVerifyLenDist(in, inend, i, dist, leng);
       ZopfliStoreLitLenDist(leng, dist, store);
     } else {
diff --git a/squeeze.c b/squeeze.c
index 7558b34..09e7e2e 100644
--- a/squeeze.c
+++ b/squeeze.c
@@ -486,6 +486,9 @@ void ZopfliLZ77Optimal(ZopfliBlockState *s,
                    &currentstore);
     cost = ZopfliCalculateBlockSize(currentstore.litlens, currentstore.dists,
                                     0, currentstore.size, 2);
+    if (s->options->verbose_more || (s->options->verbose && cost < bestcost)) {
+      fprintf(stderr, "Iteration %d: %d bit\n", i, (int) cost);
+    }
     if (cost < bestcost) {
       /* Copy to the output store. */
       ZopfliCopyLZ77Store(&currentstore, store);
diff --git a/util.c b/util.c
index b7ee2a0..d207145 100644
--- a/util.c
+++ b/util.c
@@ -205,6 +205,7 @@ int ZopfliGetLengthSymbol(int l) {
 
 void ZopfliInitOptions(ZopfliOptions* options) {
   options->verbose = 0;
+  options->verbose_more = 0;
   options->numiterations = 15;
   options->blocksplitting = 1;
   options->blocksplittinglast = 0;
diff --git a/zlib_container.c b/zlib_container.c
index 9a21231..5b7d0aa 100644
--- a/zlib_container.c
+++ b/zlib_container.c
@@ -72,8 +72,8 @@ void ZopfliZlibCompress(const ZopfliOptions* options,
 
   if (options->verbose) {
     fprintf(stderr,
-            "Original Size: %d, Compressed: %d, Compression: %f%% Removed\n",
+            "Original Size: %d, Zlib: %d, Compression: %f%% Removed\n",
             (int)insize, (int)*outsize,
-            100.0f * (float)(insize - *outsize) / (float)insize);
+            100.0 * (double)(insize - *outsize) / (double)insize);
   }
 }
diff --git a/zopfli.h b/zopfli.h
index f520b1e..1388501 100644
--- a/zopfli.h
+++ b/zopfli.h
@@ -1,8 +1,23 @@
 /*
-Copyright 2013 Google Inc. All Rights Reserved.
-Author: lode@google.com (Lode Vandevenne)
+Copyright 2011 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Author: lode.vandevenne@gmail.com (Lode Vandevenne)
+Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala)
 */
 
+
 #ifndef UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
 #define UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
 
@@ -15,6 +30,9 @@ typedef struct ZopfliOptions {
   /* Whether to print output */
   int verbose;
 
+  /* Whether to print more detailed output */
+  int verbose_more;
+
   /*
   Maximum amount of times to rerun forward and backward pass to optimize LZ77
   compression cost. Good values: 10, 15 for small files, 5 for files over
diff --git a/zopfli_bin.c b/zopfli_bin.c
index c649cf6..8a147ef 100644
--- a/zopfli_bin.c
+++ b/zopfli_bin.c
@@ -135,44 +135,43 @@ int main(int argc, char* argv[]) {
   ZopfliInitOptions(&options);
 
   for (i = 1; i < argc; i++) {
-    if (StringsEqual(argv[i], "-v")) options.verbose = 1;
-    else if (StringsEqual(argv[i], "-c")) output_to_stdout = 1;
-    else if (StringsEqual(argv[i], "--deflate")) {
+    const char* arg = argv[i];
+    if (StringsEqual(arg, "-v")) options.verbose = 1;
+    else if (StringsEqual(arg, "-c")) output_to_stdout = 1;
+    else if (StringsEqual(arg, "--deflate")) {
       output_type = ZOPFLI_FORMAT_DEFLATE;
     }
-    else if (StringsEqual(argv[i], "--zlib")) output_type = ZOPFLI_FORMAT_ZLIB;
-    else if (StringsEqual(argv[i], "--gzip")) output_type = ZOPFLI_FORMAT_GZIP;
-    else if (StringsEqual(argv[i], "--i5")) options.numiterations = 5;
-    else if (StringsEqual(argv[i], "--i10")) options.numiterations = 10;
-    else if (StringsEqual(argv[i], "--i15")) options.numiterations = 15;
-    else if (StringsEqual(argv[i], "--i25")) options.numiterations = 25;
-    else if (StringsEqual(argv[i], "--i50")) options.numiterations = 50;
-    else if (StringsEqual(argv[i], "--i100")) options.numiterations = 100;
-    else if (StringsEqual(argv[i], "--i250")) options.numiterations = 250;
-    else if (StringsEqual(argv[i], "--i500")) options.numiterations = 500;
-    else if (StringsEqual(argv[i], "--i1000")) options.numiterations = 1000;
-    else if (StringsEqual(argv[i], "-h")) {
-      fprintf(stderr, "Usage: zopfli [OPTION]... FILE\n"
+    else if (StringsEqual(arg, "--zlib")) output_type = ZOPFLI_FORMAT_ZLIB;
+    else if (StringsEqual(arg, "--gzip")) output_type = ZOPFLI_FORMAT_GZIP;
+    else if (StringsEqual(arg, "--splitlast")) options.blocksplittinglast = 1;
+    else if (arg[0] == '-' && arg[1] == '-' && arg[2] == 'i'
+        && arg[3] >= '0' && arg[3] <= '9') {
+      options.numiterations = atoi(arg + 3);
+    }
+    else if (StringsEqual(arg, "-h")) {
+      fprintf(stderr,
+          "Usage: zopfli [OPTION]... FILE\n"
           "  -h    gives this help\n"
           "  -c    write the result on standard output, instead of disk"
           " filename + '.gz'\n"
           "  -v    verbose mode\n"
-          "  --gzip  output to gzip format (default)\n"
-          "  --deflate  output to deflate format instead of gzip\n"
-          "  --zlib  output to zlib format instead of gzip\n");
-      fprintf(stderr, "  --i5  less compression, but faster\n"
-          "  --i10  less compression, but faster\n"
-          "  --i15  default compression, 15 iterations\n"
-          "  --i25  more compression, but slower\n"
-          "  --i50  more compression, but slower\n"
-          "  --i100  more compression, but slower\n"
-          "  --i250  more compression, but slower\n"
-          "  --i500  more compression, but slower\n"
-          "  --i1000  more compression, but slower\n");
+          "  --i#  perform # iterations (default 15). More gives"
+          " more compression but is slower."
+          " Examples: --i10, --i50, --i1000\n");
+      fprintf(stderr,
+          "  --gzip        output to gzip format (default)\n"
+          "  --zlib        output to zlib format instead of gzip\n"
+          "  --deflate     output to deflate format instead of gzip\n"
+          "  --splitlast   do block splitting last instead of first\n");
       return 0;
     }
   }
 
+  if (options.numiterations < 1) {
+    fprintf(stderr, "Error: must have 1 or more iterations");
+    return 0;
+  }
+
   for (i = 1; i < argc; i++) {
     if (argv[i][0] != '-') {
       char* outfilename;
diff --git a/zopfli_lib.c b/zopfli_lib.c
index 561d017..b2280e8 100644
--- a/zopfli_lib.c
+++ b/zopfli_lib.c
@@ -1,6 +1,20 @@
 /*
-Copyright 2013 Google Inc. All Rights Reserved.
-Author: lode@google.com (Lode Vandevenne)
+Copyright 2011 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Author: lode.vandevenne@gmail.com (Lode Vandevenne)
+Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala)
 */
 
 #include "zopfli.h"