michael@0: /*
michael@0:  *  Copyright (c) 2011 The WebM project authors. All Rights Reserved.
michael@0:  *
michael@0:  *  Use of this source code is governed by a BSD-style license
michael@0:  *  that can be found in the LICENSE file in the root of the source
michael@0:  *  tree. An additional intellectual property rights grant can be found
michael@0:  *  in the file PATENTS.  All contributing project authors may
michael@0:  *  be found in the AUTHORS file in the root of the source tree.
michael@0:  */
michael@0: #include <assert.h>
michael@0: #include <stdlib.h>
michael@0: #include "vpx_config.h"
michael@0: #include "lookahead.h"
michael@0: #include "vp8/common/extend.h"
michael@0: 
michael@0: #define MAX_LAG_BUFFERS (CONFIG_REALTIME_ONLY? 1 : 25)
michael@0: 
michael@0: struct lookahead_ctx
michael@0: {
michael@0:     unsigned int max_sz;         /* Absolute size of the queue */
michael@0:     unsigned int sz;             /* Number of buffers currently in the queue */
michael@0:     unsigned int read_idx;       /* Read index */
michael@0:     unsigned int write_idx;      /* Write index */
michael@0:     struct lookahead_entry *buf; /* Buffer list */
michael@0: };
michael@0: 
michael@0: 
michael@0: /* Return the buffer at the given absolute index and increment the index */
michael@0: static struct lookahead_entry *
michael@0: pop(struct lookahead_ctx *ctx,
michael@0:     unsigned int         *idx)
michael@0: {
michael@0:     unsigned int            index = *idx;
michael@0:     struct lookahead_entry *buf = ctx->buf + index;
michael@0: 
michael@0:     assert(index < ctx->max_sz);
michael@0:     if(++index >= ctx->max_sz)
michael@0:         index -= ctx->max_sz;
michael@0:     *idx = index;
michael@0:     return buf;
michael@0: }
michael@0: 
michael@0: 
michael@0: void
michael@0: vp8_lookahead_destroy(struct lookahead_ctx *ctx)
michael@0: {
michael@0:     if(ctx)
michael@0:     {
michael@0:         if(ctx->buf)
michael@0:         {
michael@0:             unsigned int i;
michael@0: 
michael@0:             for(i = 0; i < ctx->max_sz; i++)
michael@0:                 vp8_yv12_de_alloc_frame_buffer(&ctx->buf[i].img);
michael@0:             free(ctx->buf);
michael@0:         }
michael@0:         free(ctx);
michael@0:     }
michael@0: }
michael@0: 
michael@0: 
michael@0: struct lookahead_ctx*
michael@0: vp8_lookahead_init(unsigned int width,
michael@0:                    unsigned int height,
michael@0:                    unsigned int depth)
michael@0: {
michael@0:     struct lookahead_ctx *ctx = NULL;
michael@0:     unsigned int i;
michael@0: 
michael@0:     /* Clamp the lookahead queue depth */
michael@0:     if(depth < 1)
michael@0:         depth = 1;
michael@0:     else if(depth > MAX_LAG_BUFFERS)
michael@0:         depth = MAX_LAG_BUFFERS;
michael@0: 
michael@0:     /* Keep last frame in lookahead buffer by increasing depth by 1.*/
michael@0:     depth += 1;
michael@0: 
michael@0:     /* Align the buffer dimensions */
michael@0:     width = (width + 15) & ~15;
michael@0:     height = (height + 15) & ~15;
michael@0: 
michael@0:     /* Allocate the lookahead structures */
michael@0:     ctx = calloc(1, sizeof(*ctx));
michael@0:     if(ctx)
michael@0:     {
michael@0:         ctx->max_sz = depth;
michael@0:         ctx->buf = calloc(depth, sizeof(*ctx->buf));
michael@0:         if(!ctx->buf)
michael@0:             goto bail;
michael@0:         for(i=0; i<depth; i++)
michael@0:             if (vp8_yv12_alloc_frame_buffer(&ctx->buf[i].img,
michael@0:                                             width, height, VP8BORDERINPIXELS))
michael@0:                 goto bail;
michael@0:     }
michael@0:     return ctx;
michael@0: bail:
michael@0:     vp8_lookahead_destroy(ctx);
michael@0:     return NULL;
michael@0: }
michael@0: 
michael@0: 
michael@0: int
michael@0: vp8_lookahead_push(struct lookahead_ctx *ctx,
michael@0:                    YV12_BUFFER_CONFIG   *src,
michael@0:                    int64_t               ts_start,
michael@0:                    int64_t               ts_end,
michael@0:                    unsigned int          flags,
michael@0:                    unsigned char        *active_map)
michael@0: {
michael@0:     struct lookahead_entry* buf;
michael@0:     int row, col, active_end;
michael@0:     int mb_rows = (src->y_height + 15) >> 4;
michael@0:     int mb_cols = (src->y_width + 15) >> 4;
michael@0: 
michael@0:     if(ctx->sz + 2 > ctx->max_sz)
michael@0:         return 1;
michael@0:     ctx->sz++;
michael@0:     buf = pop(ctx, &ctx->write_idx);
michael@0: 
michael@0:     /* Only do this partial copy if the following conditions are all met:
michael@0:      * 1. Lookahead queue has has size of 1.
michael@0:      * 2. Active map is provided.
michael@0:      * 3. This is not a key frame, golden nor altref frame.
michael@0:      */
michael@0:     if (ctx->max_sz == 1 && active_map && !flags)
michael@0:     {
michael@0:         for (row = 0; row < mb_rows; ++row)
michael@0:         {
michael@0:             col = 0;
michael@0: 
michael@0:             while (1)
michael@0:             {
michael@0:                 /* Find the first active macroblock in this row. */
michael@0:                 for (; col < mb_cols; ++col)
michael@0:                 {
michael@0:                     if (active_map[col])
michael@0:                         break;
michael@0:                 }
michael@0: 
michael@0:                 /* No more active macroblock in this row. */
michael@0:                 if (col == mb_cols)
michael@0:                     break;
michael@0: 
michael@0:                 /* Find the end of active region in this row. */
michael@0:                 active_end = col;
michael@0: 
michael@0:                 for (; active_end < mb_cols; ++active_end)
michael@0:                 {
michael@0:                     if (!active_map[active_end])
michael@0:                         break;
michael@0:                 }
michael@0: 
michael@0:                 /* Only copy this active region. */
michael@0:                 vp8_copy_and_extend_frame_with_rect(src, &buf->img,
michael@0:                                                     row << 4,
michael@0:                                                     col << 4, 16,
michael@0:                                                     (active_end - col) << 4);
michael@0: 
michael@0:                 /* Start again from the end of this active region. */
michael@0:                 col = active_end;
michael@0:             }
michael@0: 
michael@0:             active_map += mb_cols;
michael@0:         }
michael@0:     }
michael@0:     else
michael@0:     {
michael@0:         vp8_copy_and_extend_frame(src, &buf->img);
michael@0:     }
michael@0:     buf->ts_start = ts_start;
michael@0:     buf->ts_end = ts_end;
michael@0:     buf->flags = flags;
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: 
michael@0: struct lookahead_entry*
michael@0: vp8_lookahead_pop(struct lookahead_ctx *ctx,
michael@0:                   int                   drain)
michael@0: {
michael@0:     struct lookahead_entry* buf = NULL;
michael@0: 
michael@0:     if(ctx->sz && (drain || ctx->sz == ctx->max_sz - 1))
michael@0:     {
michael@0:         buf = pop(ctx, &ctx->read_idx);
michael@0:         ctx->sz--;
michael@0:     }
michael@0:     return buf;
michael@0: }
michael@0: 
michael@0: 
michael@0: struct lookahead_entry*
michael@0: vp8_lookahead_peek(struct lookahead_ctx *ctx,
michael@0:                    unsigned int          index,
michael@0:                    int                   direction)
michael@0: {
michael@0:     struct lookahead_entry* buf = NULL;
michael@0: 
michael@0:     if (direction == PEEK_FORWARD)
michael@0:     {
michael@0:         assert(index < ctx->max_sz - 1);
michael@0:         if(index < ctx->sz)
michael@0:         {
michael@0:             index += ctx->read_idx;
michael@0:             if(index >= ctx->max_sz)
michael@0:                 index -= ctx->max_sz;
michael@0:             buf = ctx->buf + index;
michael@0:         }
michael@0:     }
michael@0:     else if (direction == PEEK_BACKWARD)
michael@0:     {
michael@0:         assert(index == 1);
michael@0: 
michael@0:         if(ctx->read_idx == 0)
michael@0:             index = ctx->max_sz - 1;
michael@0:         else
michael@0:             index = ctx->read_idx - index;
michael@0:         buf = ctx->buf + index;
michael@0:     }
michael@0: 
michael@0:     return buf;
michael@0: }
michael@0: 
michael@0: 
michael@0: unsigned int
michael@0: vp8_lookahead_depth(struct lookahead_ctx *ctx)
michael@0: {
michael@0:     return ctx->sz;
michael@0: }