options: set minimum for "threads" to zero

[ffmpeg] / libavcodec / flashsvenc.c

diff --git a/libavcodec/flashsvenc.c b/libavcodec/flashsvenc.c
index 7082040670d45f234e353b5640f496e9dfcc46d0..81aa5b6bfb4b08454c108a42c81471adb5bc8e76 100644 (file)
--- a/libavcodec/flashsvenc.c
+++ b/libavcodec/flashsvenc.c
@@ -27,22 +27,13 @@
  * Flash Screen Video encoder
  * @author Alex Beregszaszi
  * @author Benjamin Larsson
+ *
+ * A description of the bitstream format for Flash Screen Video version 1/2
+ * is part of the SWF File Format Specification (version 10), which can be
+ * downloaded from http://www.adobe.com/devnet/swf.html.
  */
 
-/* Bitstream description
- * The picture is divided into blocks that are zlib-compressed.
- *
- * The decoder is fed complete frames, the frameheader contains:
- *  4 bits of block width
- * 12 bits of frame width
- *  4 bits of block height
- * 12 bits of frame height
- *
- * Directly after the header are the compressed blocks. The blocks
- * have their compressed size represented with 16 bits in the beginning.
- * If the size = 0 then the block is unchanged from the previous frame.
- * All blocks are decompressed until the buffer is consumed.
- *
+/*
  * Encoding ideas: A basic encoder would just use a fixed block size.
  * Block sizes can be multiples of 16, from 16 to 256. The blocks don't
  * have to be quadratic. A brute force search with a set of different
@@ -156,34 +147,36 @@ static int encode_bitstream(FlashSVContext *s, AVFrame *p, uint8_t *buf,
     /* loop over all block columns */
     for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
 
-        int hp = j * block_height; // horizontal position in frame
-        int hs = (j < v_blocks) ? block_height : v_part; // size of block
+        int y_pos = j * block_height; // vertical position in frame
+        int cur_blk_height = (j < v_blocks) ? block_height : v_part;
 
         /* loop over all block rows */
         for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
-            int wp  = i * block_width; // vertical position in frame
-            int ws  = (i < h_blocks) ? block_width : h_part; // size of block
+            int x_pos = i * block_width; // horizontal position in frame
+            int cur_blk_width = (i < h_blocks) ? block_width : h_part;
             int ret = Z_OK;
             uint8_t *ptr = buf + buf_pos;
 
             /* copy the block to the temp buffer before compression
              * (if it differs from the previous frame's block) */
             res = copy_region_enc(p->data[0], s->tmpblock,
-                                  s->image_height - (hp + hs + 1),
-                                  wp, hs, ws, p->linesize[0], previous_frame);
+                                  s->image_height - (y_pos + cur_blk_height + 1),
+                                  x_pos, cur_blk_height, cur_blk_width,
+                                  p->linesize[0], previous_frame);
 
             if (res || *I_frame) {
                 unsigned long zsize = 3 * block_width * block_height;
-                ret   = compress2(ptr + 2, &zsize, s->tmpblock, 3 * ws * hs, 9);
+                ret = compress2(ptr + 2, &zsize, s->tmpblock,
+                                3 * cur_blk_width * cur_blk_height, 9);
 
                 //ret = deflateReset(&s->zstream);
                 if (ret != Z_OK)
                     av_log(s->avctx, AV_LOG_ERROR,
                            "error while compressing block %dx%d\n", i, j);
 
-                bytestream_put_be16(&ptr, (unsigned int) zsize);
+                bytestream_put_be16(&ptr, zsize);
                 buf_pos += zsize + 2;
-                av_dlog(avctx, "buf_pos = %d\n", buf_pos);
+                av_dlog(s->avctx, "buf_pos = %d\n", buf_pos);
             } else {
                 pred_blocks++;
                 bytestream_put_be16(&ptr, 0);