[FFmpeg-devel,2/3] libavcodec/cinepakenc.c: comments style cleanup

Submitted by u-9iep@aetey.se on Jan. 29, 2017, 5:43 p.m.

Details

Message ID 20170129174323.GR1516@example.net
State New
Headers show

Commit Message

u-9iep@aetey.se Jan. 29, 2017, 5:43 p.m.
Attaching the new version.

Regards,
Rune
From e6719743b78862f897133d3f69a5e88a6a9a803e Mon Sep 17 00:00:00 2001
From: Rl <addr-see-the-website@aetey.se>
Date: Sun, 29 Jan 2017 18:14:19 +0100
Subject: [PATCH 2/3] libavcodec/cinepakenc.c: comments style cleanup

Avoid the present mixture of comment styles (C vs C++)
by converting to the traditional C style.
---
 libavcodec/cinepakenc.c | 340 +++++++++++++++++++++++++++---------------------
 1 file changed, 192 insertions(+), 148 deletions(-)

Patch hide | download patch | download mbox

diff --git a/libavcodec/cinepakenc.c b/libavcodec/cinepakenc.c
index a28f669070..8c27c2a1aa 100644
--- a/libavcodec/cinepakenc.c
+++ b/libavcodec/cinepakenc.c
@@ -80,22 +80,24 @@  OTHER DEALINGS IN THE SOFTWARE.
 #define STRIP_HEADER_SIZE 12
 #define CHUNK_HEADER_SIZE 4
 
-#define MB_SIZE 4           //4x4 MBs
+#define MB_SIZE 4           /* 4x4 MBs */
 #define MB_AREA (MB_SIZE*MB_SIZE)
 
-#define VECTOR_MAX 6        //six or four entries per vector depending on format
-#define CODEBOOK_MAX 256    //size of a codebook
+#define VECTOR_MAX 6        /* six or four entries per vector depending on format */
+#define CODEBOOK_MAX 256    /* size of a codebook */
 
-#define MAX_STRIPS  32      //Note: having fewer choices regarding the number of strips speeds up encoding (obviously)
-#define MIN_STRIPS  1       //Note: having more strips speeds up encoding the frame (this is less obvious)
-// MAX_STRIPS limits the maximum quality you can reach
-//            when you want high quality on high resolutions,
-// MIN_STRIPS limits the minimum efficiently encodable bit rate
-//            on low resolutions
-// the numbers are only used for brute force optimization for the first frame,
-// for the following frames they are adaptively readjusted
-// NOTE the decoder in ffmpeg has its own arbitrary limitation on the number
-// of strips, currently 32
+#define MAX_STRIPS  32      /* Note: having fewer choices regarding the number of strips speeds up encoding (obviously) */
+#define MIN_STRIPS  1       /* Note: having more strips speeds up encoding the frame (this is less obvious) */
+/*
+ * MAX_STRIPS limits the maximum quality you can reach
+ *            when you want high quality on high resolutions,
+ * MIN_STRIPS limits the minimum efficiently encodable bit rate
+ *            on low resolutions
+ * the numbers are only used for brute force optimization for the first frame,
+ * for the following frames they are adaptively readjusted
+ * NOTE the decoder in ffmpeg has its own arbitrary limitation on the number
+ * of strips, currently 32
+ */
 
 typedef enum {
     MODE_V1_ONLY = 0,
@@ -114,12 +116,12 @@  typedef enum {
 } mb_encoding;
 
 typedef struct {
-    int v1_vector;                  //index into v1 codebook
-    int v1_error;                   //error when using V1 encoding
-    int v4_vector[4];               //indices into v4 codebook
-    int v4_error;                   //error when using V4 encoding
-    int skip_error;                 //error when block is skipped (aka copied from last frame)
-    mb_encoding best_encoding;      //last result from calculate_mode_score()
+    int v1_vector;                 /* index into v1 codebook */
+    int v1_error;                  /* error when using V1 encoding */
+    int v4_vector[4];              /* indices into v4 codebook */
+    int v4_error;                  /* error when using V4 encoding */
+    int skip_error;                /* error when block is skipped (aka copied from last frame) */
+    mb_encoding best_encoding;     /* last result from calculate_mode_score() */
 } mb_info;
 
 typedef struct {
@@ -146,15 +148,15 @@  typedef struct {
     uint64_t lambda;
     int *codebook_input;
     int *codebook_closest;
-    mb_info *mb;                                //MB RD state
-    int min_strips;          //the current limit
-    int max_strips;          //the current limit
+    mb_info *mb;                                /* MB RD state */
+    int min_strips;          /* the current limit */
+    int max_strips;          /* the current limit */
 #ifdef CINEPAKENC_DEBUG
-    mb_info *best_mb;                           //TODO: remove. only used for printing stats
+    mb_info *best_mb;                           /* TODO: remove. only used for printing stats */
     int num_v1_mode, num_v4_mode, num_mc_mode;
     int num_v1_encs, num_v4_encs, num_skips;
 #endif
-// options
+/* options */
     int max_extra_cb_iterations;
     int skip_empty_cb;
     int min_min_strips;
@@ -219,10 +221,12 @@  static av_cold int cinepak_encode_init(AVCodecContext *avctx)
 
     mb_count = avctx->width * avctx->height / MB_AREA;
 
-    //the largest possible chunk is 0x31 with all MBs encoded in V4 mode
-    //and full codebooks being replaced in INTER mode,
-    // which is 34 bits per MB
-    //and 2*256 extra flag bits per strip
+    /*
+     * the largest possible chunk is 0x31 with all MBs encoded in V4 mode
+     * and full codebooks being replaced in INTER mode,
+     * which is 34 bits per MB
+     * and 2*256 extra flag bits per strip
+     */
     strip_buf_size = STRIP_HEADER_SIZE + 3 * CHUNK_HEADER_SIZE + 2 * VECTOR_MAX * CODEBOOK_MAX + 4 * (mb_count + (mb_count + 15) / 16) + (2 * CODEBOOK_MAX)/8;
 
     frame_buf_size = CVID_HEADER_SIZE + s->max_max_strips * strip_buf_size;
@@ -250,7 +254,7 @@  static av_cold int cinepak_encode_init(AVCodecContext *avctx)
     s->keyint = avctx->keyint_min;
     s->pix_fmt = avctx->pix_fmt;
 
-    //set up AVFrames
+    /* set up AVFrames */
     s->last_frame->data[0]        = s->pict_bufs[0];
     s->last_frame->linesize[0]    = s->w;
     s->best_frame->data[0]        = s->pict_bufs[1];
@@ -314,7 +318,7 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
 #endif
 )
 {
-    //score = FF_LAMBDA_SCALE * error + lambda * bits
+    /* score = FF_LAMBDA_SCALE * error + lambda * bits */
     int x;
     int entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
     int mb_count = s->w * h / MB_AREA;
@@ -324,7 +328,9 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
                    (info->v4_size ? CHUNK_HEADER_SIZE + info->v4_size * entry_size : 0) +
                    CHUNK_HEADER_SIZE) << 3;
 
-    //av_log(s->avctx, AV_LOG_INFO, "sizes %3i %3i -> %9"PRId64" score mb_count %i", info->v1_size, info->v4_size, ret, mb_count);
+/****
+    av_log(s->avctx, AV_LOG_INFO, "sizes %3i %3i -> %9"PRId64" score mb_count %i", info->v1_size, info->v4_size, ret, mb_count);
+****/
 
 #ifdef CINEPAK_REPORT_SERR
     *serr = 0;
@@ -332,26 +338,26 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
 
     switch(info->mode) {
     case MODE_V1_ONLY:
-        //one byte per MB
+        /* one byte per MB */
         ret += s->lambda * 8 * mb_count;
 
-// while calculating we assume all blocks are ENC_V1
+/* while calculating we assume all blocks are ENC_V1 */
         for(x = 0; x < mb_count; x++) {
             mb = &s->mb[x];
             ret += FF_LAMBDA_SCALE * mb->v1_error;
 #ifdef CINEPAK_REPORT_SERR
             *serr += mb->v1_error;
 #endif
-// this function is never called for report in MODE_V1_ONLY
-//            if(!report)
+/* this function is never called for report in MODE_V1_ONLY */
+/*            if(!report) */
             mb->best_encoding = ENC_V1;
         }
 
         break;
     case MODE_V1_V4:
-        //9 or 33 bits per MB
+        /* 9 or 33 bits per MB */
         if(report) {
-// no moves between the corresponding training sets are allowed
+/* no moves between the corresponding training sets are allowed */
             *training_set_v1_shrunk = *training_set_v4_shrunk = 0;
             for(x = 0; x < mb_count; x++) {
                 int mberr;
@@ -365,7 +371,7 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
                 *serr += mberr;
 #endif
             }
-        } else { // find best mode per block
+        } else { /* find best mode per block */
             for(x = 0; x < mb_count; x++) {
                 mb = &s->mb[x];
                 score1 = s->lambda * 9  + FF_LAMBDA_SCALE * mb->v1_error;
@@ -389,13 +395,13 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
 
         break;
     case MODE_MC:
-        //1, 10 or 34 bits per MB
+        /* 1, 10 or 34 bits per MB */
         if(report) {
             int v1_shrunk = 0, v4_shrunk = 0;
             for(x = 0; x < mb_count; x++) {
                 mb = &s->mb[x];
-// it is OK to move blocks to ENC_SKIP here
-// but not to any codebook encoding!
+/* it is OK to move blocks to ENC_SKIP here */
+/* but not to any codebook encoding! */
                 score1 = s->lambda * 1  + FF_LAMBDA_SCALE * mb->skip_error;
                 if(mb->best_encoding == ENC_SKIP) {
                     ret += score1;
@@ -434,7 +440,7 @@  static int64_t calculate_mode_score(CinepakEncContext *s, int h, strip_info *inf
             }
             *training_set_v1_shrunk = v1_shrunk;
             *training_set_v4_shrunk = v4_shrunk;
-        } else { // find best mode per block
+        } else { /* find best mode per block */
             for(x = 0; x < mb_count; x++) {
                 mb = &s->mb[x];
                 score1 = s->lambda * 1  + FF_LAMBDA_SCALE * mb->skip_error;
@@ -479,8 +485,8 @@  static int write_chunk_header(unsigned char *buf, int chunk_type, int chunk_size
 static int encode_codebook(CinepakEncContext *s, int *codebook, int size, int chunk_type_yuv, int chunk_type_gray, unsigned char *buf)
 {
     int x, y, ret, entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
-    int incremental_codebook_replacement_mode = 0; // hardcoded here,
-                // the compiler should notice that this is a constant -- rl
+    int incremental_codebook_replacement_mode = 0; /* hardcoded here, */
+                /* the compiler should notice that this is a constant -- rl */
 
     ret = write_chunk_header(buf,
           s->pix_fmt == AV_PIX_FMT_RGB24 ?
@@ -489,11 +495,13 @@  static int encode_codebook(CinepakEncContext *s, int *codebook, int size, int ch
           entry_size * size
            + (incremental_codebook_replacement_mode?(size+31)/32*4:0) );
 
-// we do codebook encoding according to the "intra" mode
-// but we keep the "dead" code for reference in case we will want
-// to use incremental codebook updates (which actually would give us
-// "kind of" motion compensation, especially in 1 strip/frame case) -- rl
-// (of course, the code will be not useful as-is)
+/*
+ * we do codebook encoding according to the "intra" mode
+ * but we keep the "dead" code for reference in case we will want
+ * to use incremental codebook updates (which actually would give us
+ * "kind of" motion compensation, especially in 1 strip/frame case) -- rl
+ * (of course, the code will be not useful as-is)
+ */
     if(incremental_codebook_replacement_mode) {
         int flags = 0;
         int flagsind;
@@ -521,7 +529,7 @@  static int encode_codebook(CinepakEncContext *s, int *codebook, int size, int ch
     return ret;
 }
 
-//sets out to the sub picture starting at (x,y) in in
+/* sets out to the sub picture starting at (x,y) in in */
 static void get_sub_picture(CinepakEncContext *s, int x, int y,
                             uint8_t * in_data[4], int  in_linesize[4],
                             uint8_t *out_data[4], int out_linesize[4])
@@ -538,7 +546,7 @@  static void get_sub_picture(CinepakEncContext *s, int x, int y,
     }
 }
 
-//decodes the V1 vector in mb into the 4x4 MB pointed to by data
+/* decodes the V1 vector in mb into the 4x4 MB pointed to by data */
 static void decode_v1_vector(CinepakEncContext *s, uint8_t *data[4],
                              int linesize[4], int v1_vector, strip_info *info)
 {
@@ -577,7 +585,7 @@  static void decode_v1_vector(CinepakEncContext *s, uint8_t *data[4],
     }
 }
 
-//decodes the V4 vectors in mb into the 4x4 MB pointed to by data
+/* decodes the V4 vectors in mb into the 4x4 MB pointed to by data */
 static void decode_v4_vector(CinepakEncContext *s, uint8_t *data[4],
                              int linesize[4], int *v4_vector, strip_info *info)
 {
@@ -627,22 +635,24 @@  static int encode_mode(CinepakEncContext *s, int h,
 {
     int x, y, z, flags, bits, temp_size, header_ofs, ret = 0, mb_count = s->w * h / MB_AREA;
     int needs_extra_bit, should_write_temp;
-    unsigned char temp[64]; //32/2 = 16 V4 blocks at 4 B each -> 64 B
+    unsigned char temp[64]; /* 32/2 = 16 V4 blocks at 4 B each -> 64 B */
     mb_info *mb;
     uint8_t *sub_scratch_data[4] = {0}, *sub_last_data[4] = {0};
     int sub_scratch_linesize[4] = {0}, sub_last_linesize[4] = {0};
 
-    //encode codebooks
-////// MacOS vintage decoder compatibility dictates the presence of
-////// the codebook chunk even when the codebook is empty - pretty dumb...
-////// and also the certain order of the codebook chunks -- rl
+    /* encode codebooks */
+/*
+ *** MacOS vintage decoder compatibility dictates the presence of
+ *** the codebook chunk even when the codebook is empty - pretty dumb...
+ *** and also the certain order of the codebook chunks -- rl
+ */
     if(info->v4_size || !s->skip_empty_cb)
         ret += encode_codebook(s, info->v4_codebook, info->v4_size, 0x20, 0x24, buf + ret);
 
     if(info->v1_size || !s->skip_empty_cb)
         ret += encode_codebook(s, info->v1_codebook, info->v1_size, 0x22, 0x26, buf + ret);
 
-    //update scratch picture
+    /* update scratch picture */
     for(z = y = 0; y < h; y += MB_SIZE) {
         for(x = 0; x < s->w; x += MB_SIZE, z++) {
             mb = &s->mb[z];
@@ -667,7 +677,9 @@  static int encode_mode(CinepakEncContext *s, int h,
 
     switch(info->mode) {
     case MODE_V1_ONLY:
-        //av_log(s->avctx, AV_LOG_INFO, "mb_count = %i\n", mb_count);
+/****
+        av_log(s->avctx, AV_LOG_INFO, "mb_count = %i\n", mb_count);
+****/
         ret += write_chunk_header(buf + ret, 0x32, mb_count);
 
         for(x = 0; x < mb_count; x++)
@@ -675,7 +687,7 @@  static int encode_mode(CinepakEncContext *s, int h,
 
         break;
     case MODE_V1_V4:
-        //remember header position
+        /* remember header position */
         header_ofs = ret;
         ret += CHUNK_HEADER_SIZE;
 
@@ -703,7 +715,7 @@  static int encode_mode(CinepakEncContext *s, int h,
 
         break;
     case MODE_MC:
-        //remember header position
+        /* remember header position */
         header_ofs = ret;
         ret += CHUNK_HEADER_SIZE;
         flags = bits = temp_size = 0;
@@ -767,7 +779,7 @@  static int encode_mode(CinepakEncContext *s, int h,
     return ret;
 }
 
-//computes distortion of 4x4 MB in b compared to a
+/* computes distortion of 4x4 MB in b compared to a */
 static int compute_mb_distortion(CinepakEncContext *s,
                                  uint8_t *a_data[4], int a_linesize[4],
                                  uint8_t *b_data[4], int b_linesize[4])
@@ -795,7 +807,7 @@  static int compute_mb_distortion(CinepakEncContext *s,
     return ret;
 }
 
-// return the possibly adjusted size of the codebook
+/* return the possibly adjusted size of the codebook */
 #define CERTAIN(x) ((x)!=ENC_UNCERTAIN)
 static int quantize(CinepakEncContext *s, int h,
                     uint8_t *data[4], int linesize[4],
@@ -816,13 +828,13 @@  static int quantize(CinepakEncContext *s, int h,
             int *base;
 
             if(CERTAIN(encoding)) {
-// use for the training only the blocks known to be to be encoded [sic:-]
+/* use for the training only the blocks known to be to be encoded [sic:-] */
                if(s->mb[mbn].best_encoding != encoding) continue;
             }
 
             base = s->codebook_input + i*entry_size;
             if(v1mode) {
-                //subsample
+                /* subsample */
                 for(j = y2 = 0; y2 < entry_size; y2 += 2) {
                     for(x2 = 0; x2 < 4; x2 += 2, j++) {
                         plane = y2 < 4 ? 0 : 1 + (x2 >> 1);
@@ -836,7 +848,7 @@  static int quantize(CinepakEncContext *s, int h,
                     }
                 }
             } else {
-                //copy
+                /* copy */
                 for(j = y2 = 0; y2 < MB_SIZE; y2 += 2) {
                     for(x2 = 0; x2 < MB_SIZE; x2 += 2) {
                         for(k = 0; k < entry_size; k++, j++) {
@@ -858,42 +870,46 @@  static int quantize(CinepakEncContext *s, int h,
             i += v1mode ? 1 : 4;
         }
     }
-//    if(i < mbn*(v1mode ? 1 : 4)) {
-//        av_log(s->avctx, AV_LOG_INFO, "reducing training set for %s from %i to %i (encoding %i)\n", v1mode?"v1":"v4", mbn*(v1mode ? 1 : 4), i, encoding);
-//    }
+/****
+    if(i < mbn*(v1mode ? 1 : 4)) {
+        av_log(s->avctx, AV_LOG_INFO, "reducing training set for %s from %i to %i (encoding %i)\n", v1mode?"v1":"v4", mbn*(v1mode ? 1 : 4), i, encoding);
+    }
+****/
 
-    if(i == 0) // empty training set, nothing to do
+    if(i == 0) /* empty training set, nothing to do */
         return 0;
     if(i < size) {
-        //av_log(s->avctx, (CERTAIN(encoding) ? AV_LOG_ERROR : AV_LOG_INFO), "WOULD WASTE: %s cbsize %i bigger than training set size %i (encoding %i)\n", v1mode?"v1":"v4", size, i, encoding);
+/****
+        av_log(s->avctx, (CERTAIN(encoding) ? AV_LOG_ERROR : AV_LOG_INFO), "WOULD WASTE: %s cbsize %i bigger than training set size %i (encoding %i)\n", v1mode?"v1":"v4", size, i, encoding);
+****/
         size = i;
     }
 
     avpriv_init_elbg(s->codebook_input, entry_size, i, codebook, size, 1, s->codebook_closest, &s->randctx);
     avpriv_do_elbg(s->codebook_input, entry_size, i, codebook, size, 1, s->codebook_closest, &s->randctx);
 
-    //setup vq_data, which contains a single MB
+    /* setup vq_data, which contains a single MB */
     vq_data[0] = vq_pict_buf;
     vq_linesize[0] = MB_SIZE;
     vq_data[1] = &vq_pict_buf[MB_AREA];
     vq_data[2] = vq_data[1] + (MB_AREA >> 2);
     vq_linesize[1] = vq_linesize[2] = MB_SIZE >> 1;
 
-    //copy indices
+    /* copy indices */
     for(i = j = y = 0; y < h; y += MB_SIZE) {
         for(x = 0; x < s->w; x += MB_SIZE, j++) {
             mb_info *mb = &s->mb[j];
-// skip uninteresting blocks if we know their preferred encoding
+/* skip uninteresting blocks if we know their preferred encoding */
             if(CERTAIN(encoding) && mb->best_encoding != encoding)
                 continue;
 
-            //point sub_data to current MB
+            /* point sub_data to current MB */
             get_sub_picture(s, x, y, data, linesize, sub_data, sub_linesize);
 
             if(v1mode) {
                 mb->v1_vector = s->codebook_closest[i];
 
-                //fill in vq_data with V1 data
+                /* fill in vq_data with V1 data */
                 decode_v1_vector(s, vq_data, vq_linesize, mb->v1_vector, info);
 
                 mb->v1_error = compute_mb_distortion(s, sub_data, sub_linesize,
@@ -903,7 +919,7 @@  static int quantize(CinepakEncContext *s, int h,
                 for(k = 0; k < 4; k++)
                     mb->v4_vector[k] = s->codebook_closest[i+k];
 
-                //fill in vq_data with V4 data
+                /* fill in vq_data with V4 data */
                 decode_v4_vector(s, vq_data, vq_linesize, mb->v4_vector, info);
 
                 mb->v4_error = compute_mb_distortion(s, sub_data, sub_linesize,
@@ -913,10 +929,12 @@  static int quantize(CinepakEncContext *s, int h,
             i += v1mode ? 1 : 4;
         }
     }
-// check that we did it right in the beginning of the function
-    av_assert0(i >= size); // training set is no smaller than the codebook
+/* check that we did it right in the beginning of the function */
+    av_assert0(i >= size); /* training set is no smaller than the codebook */
 
-    //av_log(s->avctx, AV_LOG_INFO, "isv1 %i size= %i i= %i error %"PRId64"\n", v1mode, size, i, total_error);
+/****
+    av_log(s->avctx, AV_LOG_INFO, "isv1 %i size= %i i= %i error %"PRId64"\n", v1mode, size, i, total_error);
+****/
 
     return size;
 }
@@ -946,20 +964,24 @@  static void calculate_skip_errors(CinepakEncContext *s, int h,
 
 static void write_strip_header(CinepakEncContext *s, int y, int h, int keyframe, unsigned char *buf, int strip_size)
 {
-// actually we are exclusively using intra strip coding (how much can we win
-// otherwise? how to choose which part of a codebook to update?),
-// keyframes are different only because we disallow ENC_SKIP on them -- rl
-// (besides, the logic here used to be inverted: )
-//    buf[0] = keyframe ? 0x11: 0x10;
+/*
+ * actually we are exclusively using intra strip coding (how much can we win
+ * otherwise? how to choose which part of a codebook to update?),
+ * keyframes are different only because we disallow ENC_SKIP on them -- rl
+ * (besides, the logic here used to be inverted: )
+ *    buf[0] = keyframe ? 0x11: 0x10;
+ */
     buf[0] = keyframe ? 0x10: 0x11;
     AV_WB24(&buf[1], strip_size + STRIP_HEADER_SIZE);
-//    AV_WB16(&buf[4], y); /* using absolute y values works -- rl */
+/*    AV_WB16(&buf[4], y); *//* using absolute y values works -- rl */
     AV_WB16(&buf[4], 0); /* using relative values works as well -- rl */
     AV_WB16(&buf[6], 0);
-//    AV_WB16(&buf[8], y+h); /* using absolute y values works -- rl */
+/*    AV_WB16(&buf[8], y+h); *//* using absolute y values works -- rl */
     AV_WB16(&buf[8], h); /* using relative values works as well -- rl */
     AV_WB16(&buf[10], s->w);
-    //av_log(s->avctx, AV_LOG_INFO, "write_strip_header() %x keyframe=%d\n", buf[0], keyframe);
+/****
+    av_log(s->avctx, AV_LOG_INFO, "write_strip_header() %x keyframe=%d\n", buf[0], keyframe);
+****/
 }
 
 static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
@@ -978,7 +1000,7 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
 #endif
     int best_size = 0;
     strip_info info;
-// for codebook optimization:
+/* for codebook optimization: */
     int v1enough, v1_size, v4enough, v4_size;
     int new_v1_size, new_v4_size;
     int v1shrunk, v4shrunk;
@@ -987,31 +1009,33 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
         calculate_skip_errors(s, h, last_data, last_linesize, data, linesize,
                               &info);
 
-    //try some powers of 4 for the size of the codebooks
-    //constraint the v4 codebook to be no bigger than v1 one,
-    //(and no less than v1_size/4)
-    //thus making v1 preferable and possibly losing small details? should be ok
+    /*
+     * try some powers of 4 for the size of the codebooks,
+     * constraint the v4 codebook to be no bigger than v1 one
+     * (and no less than v1_size/4)
+     * thus making v1 preferable and possibly losing small details? should be ok
+     */
 #define SMALLEST_CODEBOOK 1
     for(v1enough = 0, v1_size = SMALLEST_CODEBOOK; v1_size <= CODEBOOK_MAX && !v1enough; v1_size <<= 2) {
         for(v4enough = 0, v4_size = 0; v4_size <= v1_size && !v4enough; v4_size = v4_size ? v4_size << 2 : v1_size >= SMALLEST_CODEBOOK << 2 ? v1_size >> 2 : SMALLEST_CODEBOOK) {
-            //try all modes
+            /* try all modes */
             for(CinepakMode mode = 0; mode < MODE_COUNT; mode++) {
-                //don't allow MODE_MC in intra frames
+                /* don't allow MODE_MC in intra frames */
                 if(keyframe && mode == MODE_MC)
                     continue;
 
                 if(mode == MODE_V1_ONLY) {
                     info.v1_size = v1_size;
-// the size may shrink even before optimizations if the input is short:
+/* the size may shrink even before optimizations if the input is short: */
                     info.v1_size = quantize(s, h, data, linesize, 1,
                                             &info, ENC_UNCERTAIN);
                     if(info.v1_size < v1_size)
-// too few eligible blocks, no sense in trying bigger sizes
+/* too few eligible blocks, no sense in trying bigger sizes */
                         v1enough = 1;
 
                     info.v4_size = 0;
-                } else { // mode != MODE_V1_ONLY
-                    // if v4 codebook is empty then only allow V1-only mode
+                } else { /* mode != MODE_V1_ONLY */
+                    /* if v4 codebook is empty then only allow V1-only mode */
                     if(!v4_size)
                         continue;
 
@@ -1020,13 +1044,13 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
                         info.v4_size = quantize(s, h, data, linesize, 0,
                                                 &info, ENC_UNCERTAIN);
                         if(info.v4_size < v4_size)
-// too few eligible blocks, no sense in trying bigger sizes
+/* too few eligible blocks, no sense in trying bigger sizes */
                             v4enough = 1;
                     }
                 }
 
                 info.mode = mode;
-// choose the best encoding per block, based on current experience
+/* choose the best encoding per block, based on current experience */
                 score = calculate_mode_score(s, h, &info, 0,
                                              &v1shrunk, &v4shrunk
 #ifdef CINEPAK_REPORT_SERR
@@ -1036,25 +1060,31 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
 
                 if(mode != MODE_V1_ONLY){
                     int extra_iterations_limit = s->max_extra_cb_iterations;
-// recompute the codebooks, omitting the extra blocks
-// we assume we _may_ come here with more blocks to encode than before
+/* recompute the codebooks, omitting the extra blocks */
+/* we assume we _may_ come here with more blocks to encode than before */
                     info.v1_size = v1_size;
                     new_v1_size = quantize(s, h, data, linesize, 1, &info, ENC_V1);
                     if(new_v1_size < info.v1_size){
-                        //av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v1 codebook to %i entries\n", mode, v1_size, v4_size, new_v1_size);
+/****
+                        av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v1 codebook to %i entries\n", mode, v1_size, v4_size, new_v1_size);
+****/
                         info.v1_size = new_v1_size;
                     }
-// we assume we _may_ come here with more blocks to encode than before
+/* we assume we _may_ come here with more blocks to encode than before */
                     info.v4_size = v4_size;
                     new_v4_size = quantize(s, h, data, linesize, 0, &info, ENC_V4);
                     if(new_v4_size < info.v4_size) {
-                        //av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v4 codebook to %i entries at first iteration\n", mode, v1_size, v4_size, new_v4_size);
+/****
+                        av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v4 codebook to %i entries at first iteration\n", mode, v1_size, v4_size, new_v4_size);
+****/
                         info.v4_size = new_v4_size;
                     }
-// calculate the resulting score
-// (do not move blocks to codebook encodings now, as some blocks may have
-// got bigger errors despite a smaller training set - but we do not
-// ever grow the training sets back)
+/*
+ * calculate the resulting score
+ * (do not move blocks to codebook encodings now, as some blocks may have
+ * got bigger errors despite a smaller training set - but we do not
+ * ever grow the training sets back)
+ */
                     for(;;) {
                         score = calculate_mode_score(s, h, &info, 1,
                                                      &v1shrunk, &v4shrunk
@@ -1062,14 +1092,16 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
 , &serr
 #endif
 );
-// do we have a reason to reiterate? if so, have we reached the limit?
+/* do we have a reason to reiterate? if so, have we reached the limit? */
                         if((!v1shrunk && !v4shrunk) || !extra_iterations_limit--) break;
-// recompute the codebooks, omitting the extra blocks
+/* recompute the codebooks, omitting the extra blocks */
                         if(v1shrunk) {
                             info.v1_size = v1_size;
                             new_v1_size = quantize(s, h, data, linesize, 1, &info, ENC_V1);
                             if(new_v1_size < info.v1_size){
-                                //av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v1 codebook to %i entries\n", mode, v1_size, v4_size, new_v1_size);
+/****
+                                av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v1 codebook to %i entries\n", mode, v1_size, v4_size, new_v1_size);
+****/
                                 info.v1_size = new_v1_size;
                             }
                         }
@@ -1077,14 +1109,18 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
                             info.v4_size = v4_size;
                             new_v4_size = quantize(s, h, data, linesize, 0, &info, ENC_V4);
                             if(new_v4_size < info.v4_size) {
-                                //av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v4 codebook to %i entries\n", mode, v1_size, v4_size, new_v4_size);
+/****
+                                av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: cut v4 codebook to %i entries\n", mode, v1_size, v4_size, new_v4_size);
+****/
                                 info.v4_size = new_v4_size;
                             }
                         }
                     }
                 }
 
-                //av_log(s->avctx, AV_LOG_INFO, "%3i %3i score = %"PRId64"\n", v1_size, v4_size, score);
+/****
+                av_log(s->avctx, AV_LOG_INFO, "%3i %3i score = %"PRId64"\n", v1_size, v4_size, score);
+****/
 
                 if(best_size == 0 || score < *best_score) {
 
@@ -1097,18 +1133,20 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
                                             last_data, last_linesize, &info,
                                             s->strip_buf + STRIP_HEADER_SIZE);
 
-                    //av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: %18"PRId64" %i B", mode, info.v1_size, info.v4_size, score, best_size);
-                    //av_log(s->avctx, AV_LOG_INFO, "\n");
+/****
+                    av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: %18"PRId64" %i B", mode, info.v1_size, info.v4_size, score, best_size);
+                    av_log(s->avctx, AV_LOG_INFO, "\n");
+****/
 #ifdef CINEPAK_REPORT_SERR
                     av_log(s->avctx, AV_LOG_INFO, "mode %i, %3i, %3i: %18"PRId64" %i B\n", mode, v1_size, v4_size, serr, best_size);
 #endif
 
 #ifdef CINEPAKENC_DEBUG
-                    //save MB encoding choices
+                    /* save MB encoding choices */
                     memcpy(s->best_mb, s->mb, mb_count*sizeof(mb_info));
 #endif
 
-                    //memcpy(strip_temp + STRIP_HEADER_SIZE, strip_temp, best_size);
+                    /* memcpy(strip_temp + STRIP_HEADER_SIZE, strip_temp, best_size); */
                     write_strip_header(s, y, h, keyframe, s->strip_buf, best_size);
 
                 }
@@ -1117,7 +1155,7 @@  static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
     }
 
 #ifdef CINEPAKENC_DEBUG
-    //gather stats. this will only work properly of MAX_STRIPS == 1
+    /* gather stats. this will only work properly of MAX_STRIPS == 1 */
     if(best_info.mode == MODE_V1_ONLY) {
         s->num_v1_mode++;
         s->num_v1_encs += s->w*h/MB_AREA;
@@ -1166,11 +1204,11 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
     int64_t best_serr = 0, serr, serr_temp;
 #endif
 
-    int best_nstrips = -1, best_size = -1; // mark as uninitialzed
+    int best_nstrips = -1, best_size = -1; /* mark as uninitialzed */
 
     if(s->pix_fmt == AV_PIX_FMT_RGB24) {
         int x;
-// build a copy of the given frame in the correct colorspace
+/* build a copy of the given frame in the correct colorspace */
         for(y = 0; y < s->h; y += 2) {
             for(x = 0; x < s->w; x += 2) {
                 uint8_t *ir[2]; int32_t r, g, b, rr, gg, bb;
@@ -1187,34 +1225,34 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
                     gg = ir[i2][i1*3+1];
                     bb = ir[i2][i1*3+2];
                     r += rr; g += gg; b += bb;
-// using fixed point arithmetic for portable repeatability, scaling by 2^23
-// "Y"
-//                    rr = 0.2857*rr + 0.5714*gg + 0.1429*bb;
+/* using fixed point arithmetic for portable repeatability, scaling by 2^23 */
+/* "Y" */
+/*                    rr = 0.2857*rr + 0.5714*gg + 0.1429*bb; */
                     rr = (2396625*rr + 4793251*gg + 1198732*bb) >> 23;
                     if(      rr <   0) rr =   0;
                     else if (rr > 255) rr = 255;
                     scratch_data[0][i1 + i2*scratch_linesize[0]] = rr;
                 }
-// let us scale down as late as possible
-//                r /= 4; g /= 4; b /= 4;
-// "U"
-//                rr = -0.1429*r - 0.2857*g + 0.4286*b;
+/* let us scale down as late as possible */
+/*                r /= 4; g /= 4; b /= 4; */
+/* "U" */
+/*                rr = -0.1429*r - 0.2857*g + 0.4286*b; */
                 rr = (-299683*r - 599156*g + 898839*b) >> 23;
                 if(      rr < -128) rr = -128;
                 else if (rr >  127) rr =  127;
-                scratch_data[1][0] = rr + 128; // quantize needs unsigned
-// "V"
-//                rr = 0.3571*r - 0.2857*g - 0.0714*b;
+                scratch_data[1][0] = rr + 128; /* quantize needs unsigned */
+/* "V" */
+/*                rr = 0.3571*r - 0.2857*g - 0.0714*b; */
                 rr = (748893*r - 599156*g - 149737*b) >> 23;
                 if(      rr < -128) rr = -128;
                 else if (rr >  127) rr =  127;
-                scratch_data[2][0] = rr + 128; // quantize needs unsigned
+                scratch_data[2][0] = rr + 128; /* quantize needs unsigned */
             }
         }
     }
 
-    //would be nice but quite certainly incompatible with vintage players:
-    // support encoding zero strips (meaning skip the whole frame)
+    /* would be nice but quite certainly incompatible with vintage players: */
+    /* support encoding zero strips (meaning skip the whole frame) */
     for(num_strips = s->min_strips; num_strips <= s->max_strips && num_strips <= s->h / MB_SIZE; num_strips++) {
         score = 0;
         size = 0;
@@ -1225,13 +1263,13 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
         for(y = 0, strip = 1; y < s->h; strip++, y = nexty) {
             int strip_height;
 
-            nexty = strip * s->h / num_strips; // <= s->h
-            //make nexty the next multiple of 4 if not already there
+            nexty = strip * s->h / num_strips; /* <= s->h */
+            /* make nexty the next multiple of 4 if not already there */
             if(nexty & 3)
                 nexty += 4 - (nexty & 3);
 
             strip_height = nexty - y;
-            if(strip_height <= 0) { // can this ever happen?
+            if(strip_height <= 0) { /* can this ever happen? */
                 av_log(s->avctx, AV_LOG_INFO, "skipping zero height strip %i of %i\n", strip, num_strips);
                 continue;
             }
@@ -1266,8 +1304,10 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
             serr += serr_temp;
 #endif
             size += temp_size;
-            //av_log(s->avctx, AV_LOG_INFO, "strip %d, isakeyframe=%d", strip, isakeyframe);
-            //av_log(s->avctx, AV_LOG_INFO, "\n");
+/****
+            av_log(s->avctx, AV_LOG_INFO, "strip %d, isakeyframe=%d", strip, isakeyframe);
+            av_log(s->avctx, AV_LOG_INFO, "\n");
+****/
         }
 
         if(best_score == 0 || score < best_score) {
@@ -1276,7 +1316,9 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
             best_serr = serr;
 #endif
             best_size = size + write_cvid_header(s, s->frame_buf, num_strips, size, isakeyframe);
-            //av_log(s->avctx, AV_LOG_INFO, "best number of strips so far: %2i, %12"PRId64", %i B\n", num_strips, score, best_size);
+/****
+            av_log(s->avctx, AV_LOG_INFO, "best number of strips so far: %2i, %12"PRId64", %i B\n", num_strips, score, best_size);
+****/
 #ifdef CINEPAK_REPORT_SERR
             av_log(s->avctx, AV_LOG_INFO, "best number of strips so far: %2i, %12"PRId64", %i B\n", num_strips, serr, best_size);
 #endif
@@ -1285,23 +1327,25 @@  static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
             memcpy(buf, s->frame_buf, best_size);
             best_nstrips = num_strips;
         }
-// avoid trying too many strip numbers without a real reason
-// (this makes the processing of the very first frame faster)
+/* avoid trying too many strip numbers without a real reason */
+/* (this makes the processing of the very first frame faster) */
         if(num_strips - best_nstrips > 4)
             break;
     }
 
     av_assert0(best_nstrips >= 0 && best_size >= 0);
 
-// let the number of strips slowly adapt to the changes in the contents,
-// compared to full bruteforcing every time this will occasionally lead
-// to some r/d performance loss but makes encoding up to several times faster
+/*
+ * let the number of strips slowly adapt to the changes in the contents,
+ * compared to full bruteforcing every time this will occasionally lead
+ * to some r/d performance loss but makes encoding up to several times faster
+ */
     if(!s->strip_number_delta_range) {
-        if(best_nstrips == s->max_strips) { // let us try to step up
+        if(best_nstrips == s->max_strips) { /* let us try to step up */
             s->max_strips = best_nstrips + 1;
             if(s->max_strips >= s->max_max_strips)
                 s->max_strips = s->max_max_strips;
-        } else { // try to step down
+        } else { /* try to step down */
             s->max_strips = best_nstrips;
         }
         s->min_strips = s->max_strips - 1;