ref: 9e8efa5b189a5abf78b1bcbc8076893728129d1e
parent: 4c3d539baa456a37ebd03f11865ea597f4724355
author: Vignesh Venkatasubramanian <vigneshv@google.com>
date: Fri Oct 7 06:24:50 EDT 2016
vp9_bitstream: Encode tiles in parallel Re-use the tile worker threads to pack the bitstream in parallel on a per-tile basis. Restricting this to real-time only for now (further testing is needed to ensure this does not make 2-pass worse in any case). BUG=webm:1309 Change-Id: Ia2c982da56697756e12f02643f589189b3271d98
--- a/vp9/encoder/vp9_bitstream.c
+++ b/vp9/encoder/vp9_bitstream.c
@@ -915,6 +915,120 @@
}
}
+static int encode_tile_worker(VP9_COMP *cpi, VP9BitstreamWorkerData *data) {+ MACROBLOCKD *const xd = &data->xd;
+ vpx_start_encode(&data->bit_writer, data->dest);
+ write_modes(cpi, xd, &cpi->tile_data[data->tile_idx].tile_info,
+ &data->bit_writer, &data->tok, data->tok_end,
+ &data->max_mv_magnitude, data->interp_filter_selected);
+ assert(data->tok == data->tok_end);
+ vpx_stop_encode(&data->bit_writer);
+ return 1;
+}
+
+void vp9_bitstream_encode_tiles_buffer_dealloc(VP9_COMP *const cpi) {+ if (cpi->vp9_bitstream_worker_data) {+ int i;
+ for (i = 1; i < cpi->num_workers; ++i) {+ vpx_free(cpi->vp9_bitstream_worker_data[i].dest);
+ }
+ vpx_free(cpi->vp9_bitstream_worker_data);
+ cpi->vp9_bitstream_worker_data = NULL;
+ }
+}
+
+static int encode_tiles_buffer_alloc(VP9_COMP *const cpi) {+ int i;
+ cpi->vp9_bitstream_worker_data =
+ vpx_calloc(cpi->num_workers, sizeof(*cpi->vp9_bitstream_worker_data));
+ if (!cpi->vp9_bitstream_worker_data) return 1;
+ for (i = 1; i < cpi->num_workers; ++i) {+ cpi->vp9_bitstream_worker_data[i].dest_size =
+ cpi->oxcf.width * cpi->oxcf.height;
+ cpi->vp9_bitstream_worker_data[i].dest =
+ vpx_malloc(cpi->vp9_bitstream_worker_data[i].dest_size);
+ if (!cpi->vp9_bitstream_worker_data[i].dest) return 1;
+ }
+ return 0;
+}
+
+static size_t encode_tiles_mt(VP9_COMP *cpi, uint8_t *data_ptr) {+ const VPxWorkerInterface *const winterface = vpx_get_worker_interface();
+ VP9_COMMON *const cm = &cpi->common;
+ const int tile_cols = 1 << cm->log2_tile_cols;
+ const int num_workers = cpi->num_workers;
+ size_t total_size = 0;
+ int tile_col = 0;
+
+ if (!cpi->vp9_bitstream_worker_data ||
+ cpi->vp9_bitstream_worker_data[1].dest_size >
+ (cpi->oxcf.width * cpi->oxcf.height)) {+ vp9_bitstream_encode_tiles_buffer_dealloc(cpi);
+ if (encode_tiles_buffer_alloc(cpi)) return 0;
+ }
+
+ while (tile_col < tile_cols) {+ int i, j;
+ for (i = 0; i < num_workers && tile_col < tile_cols; ++i) {+ VPxWorker *const worker = &cpi->workers[i];
+ VP9BitstreamWorkerData *const data = &cpi->vp9_bitstream_worker_data[i];
+
+ // Populate the worker data.
+ data->xd = cpi->td.mb.e_mbd;
+ data->tile_idx = tile_col;
+ data->tok = cpi->tile_tok[0][tile_col];
+ data->tok_end = cpi->tile_tok[0][tile_col] + cpi->tok_count[0][tile_col];
+ data->max_mv_magnitude = cpi->max_mv_magnitude;
+ memset(data->interp_filter_selected, 0,
+ sizeof(data->interp_filter_selected[0][0]) * SWITCHABLE);
+
+ // First thread can directly write into the output buffer.
+ if (i == 0) {+ data->dest = data_ptr + total_size + 4;
+ }
+ worker->data1 = cpi;
+ worker->data2 = data;
+ worker->hook = (VPxWorkerHook)encode_tile_worker;
+ worker->had_error = 0;
+
+ if (i < num_workers - 1) {+ winterface->launch(worker);
+ } else {+ winterface->execute(worker);
+ }
+ ++tile_col;
+ }
+ for (j = 0; j < i; ++j) {+ VPxWorker *const worker = &cpi->workers[j];
+ VP9BitstreamWorkerData *const data =
+ (VP9BitstreamWorkerData *)worker->data2;
+ uint32_t tile_size;
+ int k;
+
+ if (!winterface->sync(worker)) return 0;
+ tile_size = data->bit_writer.pos;
+
+ // Aggregate per-thread bitstream stats.
+ cpi->max_mv_magnitude =
+ VPXMAX(cpi->max_mv_magnitude, data->max_mv_magnitude);
+ for (k = 0; k < SWITCHABLE; ++k) {+ cpi->interp_filter_selected[0][k] += data->interp_filter_selected[0][k];
+ }
+
+ // Prefix the size of the tile on all but the last.
+ if (tile_col != tile_cols || j < i - 1) {+ mem_put_be32(data_ptr + total_size, tile_size);
+ total_size += 4;
+ }
+ if (j > 0) {+ memcpy(data_ptr + total_size, data->dest, tile_size);
+ }
+ total_size += tile_size;
+ }
+ }
+ return total_size;
+}
+
static size_t encode_tiles(VP9_COMP *cpi, uint8_t *data_ptr) {VP9_COMMON *const cm = &cpi->common;
MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
@@ -928,6 +1042,14 @@
memset(cm->above_seg_context, 0,
sizeof(*cm->above_seg_context) * mi_cols_aligned_to_sb(cm->mi_cols));
+ // Encoding tiles in parallel is done only for realtime mode now. In other
+ // modes the speed up is insignificant and requires further testing to ensure
+ // that it does not make the overall process worse in any case.
+ if (cpi->oxcf.mode == REALTIME && cpi->num_workers > 1 && tile_rows == 1 &&
+ tile_cols > 1) {+ return encode_tiles_mt(cpi, data_ptr);
+ }
+
for (tile_row = 0; tile_row < tile_rows; tile_row++) { for (tile_col = 0; tile_col < tile_cols; tile_col++) {int tile_idx = tile_row * tile_cols + tile_col;
@@ -955,7 +1077,6 @@
total_size += residual_bc.pos;
}
}
-
return total_size;
}
--- a/vp9/encoder/vp9_bitstream.h
+++ b/vp9/encoder/vp9_bitstream.h
@@ -17,9 +17,27 @@
#include "vp9/encoder/vp9_encoder.h"
+typedef struct VP9BitstreamWorkerData {+ uint8_t *dest;
+ int dest_size;
+ TOKENEXTRA *tok;
+ TOKENEXTRA *tok_end;
+ vpx_writer bit_writer;
+ int tile_idx;
+ unsigned int max_mv_magnitude;
+ // The size of interp_filter_selected in VP9_COMP is actually
+ // MAX_REFERENCE_FRAMES x SWITCHABLE. But when encoding tiles, all we ever do
+ // is increment the very first index (index 0) for the first dimension. Hence
+ // this is sufficient.
+ int interp_filter_selected[1][SWITCHABLE];
+ DECLARE_ALIGNED(16, MACROBLOCKD, xd);
+} VP9BitstreamWorkerData;
+
int vp9_get_refresh_mask(VP9_COMP *cpi);
void vp9_pack_bitstream(VP9_COMP *cpi, uint8_t *dest, size_t *size);
+
+void vp9_bitstream_encode_tiles_buffer_dealloc(VP9_COMP *const cpi);
static INLINE int vp9_preserve_existing_gf(VP9_COMP *cpi) {return !cpi->multi_arf_allowed && cpi->refresh_golden_frame &&
--- a/vp9/encoder/vp9_encoder.c
+++ b/vp9/encoder/vp9_encoder.c
@@ -2030,7 +2030,10 @@
vpx_free(cpi->tile_thr_data);
vpx_free(cpi->workers);
- if (cpi->num_workers > 1) vp9_loop_filter_dealloc(&cpi->lf_row_sync);
+ if (cpi->num_workers > 1) {+ vp9_loop_filter_dealloc(&cpi->lf_row_sync);
+ vp9_bitstream_encode_tiles_buffer_dealloc(cpi);
+ }
vp9_alt_ref_aq_destroy(cpi->alt_ref_aq);
--- a/vp9/encoder/vp9_encoder.h
+++ b/vp9/encoder/vp9_encoder.h
@@ -601,6 +601,7 @@
VPxWorker *workers;
struct EncWorkerData *tile_thr_data;
VP9LfSync lf_row_sync;
+ struct VP9BitstreamWorkerData *vp9_bitstream_worker_data;
int keep_level_stats;
Vp9LevelInfo level_info;