[FFmpeg-cvslog] h261: cosmetics: Move functions to avoid forward declarations

Diego Biurrun git at videolan.org
Fri Apr 5 22:07:39 CEST 2013


ffmpeg | branch: master | Diego Biurrun <diego at biurrun.de> | Thu Apr  4 14:33:55 2013 +0200| [0404ec619d43f27b87c424aa1a572a6699fe6a31] | committer: Diego Biurrun

h261: cosmetics: Move functions to avoid forward declarations

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0404ec619d43f27b87c424aa1a572a6699fe6a31
---

 libavcodec/h261dec.c |  178 +++++++++++++++++++++++++-------------------------
 libavcodec/h261enc.c |  149 +++++++++++++++++++++---------------------
 2 files changed, 161 insertions(+), 166 deletions(-)

diff --git a/libavcodec/h261dec.c b/libavcodec/h261dec.c
index d1ce28f..4c31cf5 100644
--- a/libavcodec/h261dec.c
+++ b/libavcodec/h261dec.c
@@ -44,8 +44,6 @@ static VLC h261_mtype_vlc;
 static VLC h261_mv_vlc;
 static VLC h261_cbp_vlc;
 
-static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded);
-
 static av_cold void h261_decode_init_vlc(H261Context *h)
 {
     static int done = 0;
@@ -246,6 +244,94 @@ static int decode_mv_component(GetBitContext *gb, int v)
     return v;
 }
 
+/**
+ * Decode a macroblock.
+ * @return <0 if an error occurred
+ */
+static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
+{
+    MpegEncContext *const s = &h->s;
+    int code, level, i, j, run;
+    RLTable *rl = &h261_rl_tcoeff;
+    const uint8_t *scan_table;
+
+    /* For the variable length encoding there are two code tables, one being
+     * used for the first transmitted LEVEL in INTER, INTER + MC and
+     * INTER + MC + FIL blocks, the second for all other LEVELs except the
+     * first one in INTRA blocks which is fixed length coded with 8 bits.
+     * NOTE: The two code tables only differ in one VLC so we handle that
+     * manually. */
+    scan_table = s->intra_scantable.permutated;
+    if (s->mb_intra) {
+        /* DC coef */
+        level = get_bits(&s->gb, 8);
+        // 0 (00000000b) and -128 (10000000b) are FORBIDDEN
+        if ((level & 0x7F) == 0) {
+            av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
+                   level, s->mb_x, s->mb_y);
+            return -1;
+        }
+        /* The code 1000 0000 is not used, the reconstruction level of 1024
+         * being coded as 1111 1111. */
+        if (level == 255)
+            level = 128;
+        block[0] = level;
+        i        = 1;
+    } else if (coded) {
+        // Run  Level   Code
+        // EOB          Not possible for first level when cbp is available (that's why the table is different)
+        // 0    1       1s
+        // *    *       0*
+        int check = show_bits(&s->gb, 2);
+        i = 0;
+        if (check & 0x2) {
+            skip_bits(&s->gb, 2);
+            block[0] = (check & 0x1) ? -1 : 1;
+            i        = 1;
+        }
+    } else {
+        i = 0;
+    }
+    if (!coded) {
+        s->block_last_index[n] = i - 1;
+        return 0;
+    }
+    for (;;) {
+        code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
+        if (code < 0) {
+            av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
+                   s->mb_x, s->mb_y);
+            return -1;
+        }
+        if (code == rl->n) {
+            /* escape */
+            /* The remaining combinations of (run, level) are encoded with a
+             * 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits
+             * level. */
+            run   = get_bits(&s->gb, 6);
+            level = get_sbits(&s->gb, 8);
+        } else if (code == 0) {
+            break;
+        } else {
+            run   = rl->table_run[code];
+            level = rl->table_level[code];
+            if (get_bits1(&s->gb))
+                level = -level;
+        }
+        i += run;
+        if (i >= 64) {
+            av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n",
+                   s->mb_x, s->mb_y);
+            return -1;
+        }
+        j        = scan_table[i];
+        block[j] = level;
+        i++;
+    }
+    s->block_last_index[n] = i - 1;
+    return 0;
+}
+
 static int h261_decode_mb(H261Context *h)
 {
     MpegEncContext *const s = &h->s;
@@ -354,94 +440,6 @@ intra:
 }
 
 /**
- * Decode a macroblock.
- * @return <0 if an error occurred
- */
-static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
-{
-    MpegEncContext *const s = &h->s;
-    int code, level, i, j, run;
-    RLTable *rl = &h261_rl_tcoeff;
-    const uint8_t *scan_table;
-
-    /* For the variable length encoding there are two code tables, one being
-     * used for the first transmitted LEVEL in INTER, INTER + MC and
-     * INTER + MC + FIL blocks, the second for all other LEVELs except the
-     * first one in INTRA blocks which is fixed length coded with 8 bits.
-     * NOTE: The two code tables only differ in one VLC so we handle that
-     * manually. */
-    scan_table = s->intra_scantable.permutated;
-    if (s->mb_intra) {
-        /* DC coef */
-        level = get_bits(&s->gb, 8);
-        // 0 (00000000b) and -128 (10000000b) are FORBIDDEN
-        if ((level & 0x7F) == 0) {
-            av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
-                   level, s->mb_x, s->mb_y);
-            return -1;
-        }
-        /* The code 1000 0000 is not used, the reconstruction level of 1024
-         * being coded as 1111 1111. */
-        if (level == 255)
-            level = 128;
-        block[0] = level;
-        i        = 1;
-    } else if (coded) {
-        // Run  Level   Code
-        // EOB          Not possible for first level when cbp is available (that's why the table is different)
-        // 0    1       1s
-        // *    *       0*
-        int check = show_bits(&s->gb, 2);
-        i = 0;
-        if (check & 0x2) {
-            skip_bits(&s->gb, 2);
-            block[0] = (check & 0x1) ? -1 : 1;
-            i        = 1;
-        }
-    } else {
-        i = 0;
-    }
-    if (!coded) {
-        s->block_last_index[n] = i - 1;
-        return 0;
-    }
-    for (;;) {
-        code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
-        if (code < 0) {
-            av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
-                   s->mb_x, s->mb_y);
-            return -1;
-        }
-        if (code == rl->n) {
-            /* escape */
-            /* The remaining combinations of (run, level) are encoded with a
-             * 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits
-             * level. */
-            run   = get_bits(&s->gb, 6);
-            level = get_sbits(&s->gb, 8);
-        } else if (code == 0) {
-            break;
-        } else {
-            run   = rl->table_run[code];
-            level = rl->table_level[code];
-            if (get_bits1(&s->gb))
-                level = -level;
-        }
-        i += run;
-        if (i >= 64) {
-            av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n",
-                   s->mb_x, s->mb_y);
-            return -1;
-        }
-        j        = scan_table[i];
-        block[j] = level;
-        i++;
-    }
-    s->block_last_index[n] = i - 1;
-    return 0;
-}
-
-/**
  * Decode the H.261 picture header.
  * @return <0 if no startcode found
  */
diff --git a/libavcodec/h261enc.c b/libavcodec/h261enc.c
index f67d313..ccc1fd2 100644
--- a/libavcodec/h261enc.c
+++ b/libavcodec/h261enc.c
@@ -31,9 +31,6 @@
 #include "h261.h"
 #include "h261data.h"
 
-static void h261_encode_block(H261Context *h, int16_t *block,
-                              int n);
-
 int ff_h261_get_picture_format(int width, int height)
 {
     // QCIF
@@ -155,6 +152,79 @@ static inline int get_cbp(MpegEncContext *s, int16_t block[6][64])
     return cbp;
 }
 
+/**
+ * Encode an 8x8 block.
+ * @param block the 8x8 block
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ */
+static void h261_encode_block(H261Context *h, int16_t *block, int n)
+{
+    MpegEncContext *const s = &h->s;
+    int level, run, i, j, last_index, last_non_zero, sign, slevel, code;
+    RLTable *rl;
+
+    rl = &h261_rl_tcoeff;
+    if (s->mb_intra) {
+        /* DC coef */
+        level = block[0];
+        /* 255 cannot be represented, so we clamp */
+        if (level > 254) {
+            level    = 254;
+            block[0] = 254;
+        }
+        /* 0 cannot be represented also */
+        else if (level < 1) {
+            level    = 1;
+            block[0] = 1;
+        }
+        if (level == 128)
+            put_bits(&s->pb, 8, 0xff);
+        else
+            put_bits(&s->pb, 8, level);
+        i = 1;
+    } else if ((block[0] == 1 || block[0] == -1) &&
+               (s->block_last_index[n] > -1)) {
+        // special case
+        put_bits(&s->pb, 2, block[0] > 0 ? 2 : 3);
+        i = 1;
+    } else {
+        i = 0;
+    }
+
+    /* AC coefs */
+    last_index    = s->block_last_index[n];
+    last_non_zero = i - 1;
+    for (; i <= last_index; i++) {
+        j     = s->intra_scantable.permutated[i];
+        level = block[j];
+        if (level) {
+            run    = i - last_non_zero - 1;
+            sign   = 0;
+            slevel = level;
+            if (level < 0) {
+                sign  = 1;
+                level = -level;
+            }
+            code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/,
+                                run, level);
+            if (run == 0 && level < 16)
+                code += 1;
+            put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
+            if (code == rl->n) {
+                put_bits(&s->pb, 6, run);
+                assert(slevel != 0);
+                assert(level <= 127);
+                put_sbits(&s->pb, 8, slevel);
+            } else {
+                put_bits(&s->pb, 1, sign);
+            }
+            last_non_zero = i;
+        }
+    }
+    if (last_index > -1)
+        put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]); // EOB
+}
+
 void ff_h261_encode_mb(MpegEncContext *s, int16_t block[6][64],
                        int motion_x, int motion_y)
 {
@@ -252,79 +322,6 @@ void ff_h261_encode_init(MpegEncContext *s)
     s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
 }
 
-/**
- * Encode an 8x8 block.
- * @param block the 8x8 block
- * @param n block index (0-3 are luma, 4-5 are chroma)
- */
-static void h261_encode_block(H261Context *h, int16_t *block, int n)
-{
-    MpegEncContext *const s = &h->s;
-    int level, run, i, j, last_index, last_non_zero, sign, slevel, code;
-    RLTable *rl;
-
-    rl = &h261_rl_tcoeff;
-    if (s->mb_intra) {
-        /* DC coef */
-        level = block[0];
-        /* 255 cannot be represented, so we clamp */
-        if (level > 254) {
-            level    = 254;
-            block[0] = 254;
-        }
-        /* 0 cannot be represented also */
-        else if (level < 1) {
-            level    = 1;
-            block[0] = 1;
-        }
-        if (level == 128)
-            put_bits(&s->pb, 8, 0xff);
-        else
-            put_bits(&s->pb, 8, level);
-        i = 1;
-    } else if ((block[0] == 1 || block[0] == -1) &&
-               (s->block_last_index[n] > -1)) {
-        // special case
-        put_bits(&s->pb, 2, block[0] > 0 ? 2 : 3);
-        i = 1;
-    } else {
-        i = 0;
-    }
-
-    /* AC coefs */
-    last_index    = s->block_last_index[n];
-    last_non_zero = i - 1;
-    for (; i <= last_index; i++) {
-        j     = s->intra_scantable.permutated[i];
-        level = block[j];
-        if (level) {
-            run    = i - last_non_zero - 1;
-            sign   = 0;
-            slevel = level;
-            if (level < 0) {
-                sign  = 1;
-                level = -level;
-            }
-            code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/,
-                                run, level);
-            if (run == 0 && level < 16)
-                code += 1;
-            put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
-            if (code == rl->n) {
-                put_bits(&s->pb, 6, run);
-                assert(slevel != 0);
-                assert(level <= 127);
-                put_sbits(&s->pb, 8, slevel);
-            } else {
-                put_bits(&s->pb, 1, sign);
-            }
-            last_non_zero = i;
-        }
-    }
-    if (last_index > -1)
-        put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]); // EOB
-}
-
 FF_MPV_GENERIC_CLASS(h261)
 
 AVCodec ff_h261_encoder = {



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