AV1 levels: add max bitrate
This is a tentative implementation where the bitrate is calculated over
a 1-second rolling window.
BUG=aomedia:2332
Change-Id: I86850620e1644b6059b39a4567b73dc11e686a71
diff --git a/av1/encoder/level.c b/av1/encoder/level.c
index 6f43d06..13e14e2 100644
--- a/av1/encoder/level.c
+++ b/av1/encoder/level.c
@@ -236,6 +236,7 @@
DECODE_RATE_TOO_HIGH,
CR_TOO_SMALL,
TILE_SIZE_HEADER_RATE_TOO_HIGH,
+ BITRATE_TOO_HIGH,
TARGET_LEVEL_FAIL_IDS,
TARGET_LEVEL_OK,
@@ -260,6 +261,7 @@
"The decoded luma sample rate is too high.",
"The compression ratio is too small.",
"The product of max tile size and header rate is too high.",
+ "The bitrate is too high.",
};
void av1_init_level_info(AV1LevelInfo *level_info) {
@@ -304,6 +306,16 @@
}
}
+static double get_max_bitrate(const AV1LevelSpec *const level_spec, int tier,
+ BITSTREAM_PROFILE profile) {
+ if (level_spec->level < SEQ_LEVEL_4_0) tier = 0;
+ const double bitrate_basis =
+ (tier ? level_spec->high_mbps : level_spec->main_mbps) * 1e6;
+ const double bitrate_profile_factor =
+ profile == PROFILE_0 ? 1.0 : (profile == PROFILE_1 ? 2.0 : 3.0);
+ return bitrate_basis * bitrate_profile_factor;
+}
+
#define MAX_TILE_SIZE (4096 * 2304)
#define MIN_CROPPED_TILE_WIDTH 8
#define MIN_CROPPED_TILE_HEIGHT 8
@@ -314,9 +326,11 @@
static TARGET_LEVEL_FAIL_ID check_level_constraints(
const AV1LevelSpec *const target_level_spec,
const AV1LevelSpec *const level_spec,
- const AV1LevelStats *const level_stats, int tier, int is_still_picture) {
+ const AV1LevelStats *const level_stats, int tier, int is_still_picture,
+ BITSTREAM_PROFILE profile) {
const double min_cr = get_min_cr(target_level_spec, tier, is_still_picture,
level_spec->max_decode_rate);
+ const double max_bitrate = get_max_bitrate(target_level_spec, tier, profile);
TARGET_LEVEL_FAIL_ID fail_id = TARGET_LEVEL_OK;
do {
@@ -405,6 +419,11 @@
break;
}
+ if ((double)level_stats->max_bitrate > max_bitrate) {
+ fail_id = BITRATE_TOO_HIGH;
+ break;
+ }
+
if (target_level_spec->level > SEQ_LEVEL_5_1) {
int temporal_parallel_num;
int temporal_parallel_denom;
@@ -484,7 +503,8 @@
}
}
-static int store_frame_record(int64_t ts_start, int64_t ts_end, int pic_size,
+static int store_frame_record(int64_t ts_start, int64_t ts_end,
+ size_t encoded_size, int pic_size,
int frame_header_count, int tiles, int show_frame,
int show_existing_frame,
FrameWindowBuffer *const buffer) {
@@ -497,6 +517,7 @@
FrameRecord *const record = &buffer->buf[new_idx];
record->ts_start = ts_start;
record->ts_end = ts_end;
+ record->encoded_size_in_bytes = encoded_size;
record->pic_size = pic_size;
record->frame_header_count = frame_header_count;
record->tiles = tiles;
@@ -532,13 +553,15 @@
// Scan previously encoded frames and update level metrics accordingly.
static void scan_past_frames(const FrameWindowBuffer *const buffer,
int num_frames_to_scan,
- AV1LevelSpec *const level_spec) {
+ AV1LevelSpec *const level_spec,
+ AV1LevelStats *const level_stats) {
const int num_frames_in_buffer = buffer->num;
int index = (buffer->start + num_frames_in_buffer - 1) % FRAME_WINDOW_SIZE;
int frame_headers = 0;
int tiles = 0;
int64_t display_samples = 0;
int64_t decoded_samples = 0;
+ size_t encoded_size_in_bytes = 0;
for (int i = 0; i < AOMMIN(num_frames_in_buffer, num_frames_to_scan); ++i) {
const FrameRecord *const record = &buffer->buf[index];
if (!record->show_existing_frame) {
@@ -549,6 +572,7 @@
display_samples += record->pic_size;
}
tiles += record->tiles;
+ encoded_size_in_bytes += record->encoded_size_in_bytes;
--index;
if (index < 0) index = FRAME_WINDOW_SIZE - 1;
}
@@ -559,6 +583,8 @@
level_spec->max_decode_rate =
AOMMAX(level_spec->max_decode_rate, decoded_samples);
level_spec->max_tile_rate = AOMMAX(level_spec->max_tile_rate, tiles);
+ level_stats->max_bitrate =
+ AOMMAX(level_stats->max_bitrate, (int)encoded_size_in_bytes * 8);
}
void av1_update_level_info(AV1_COMP *cpi, size_t size, int64_t ts_start,
@@ -577,8 +603,8 @@
// Store info. of current frame into FrameWindowBuffer.
FrameWindowBuffer *const buffer = &cpi->frame_window_buffer;
- store_frame_record(ts_start, ts_end, luma_pic_size, frame_header_count, tiles,
- show_frame, show_existing_frame, buffer);
+ store_frame_record(ts_start, ts_end, size, luma_pic_size, frame_header_count,
+ tiles, show_frame, show_existing_frame, buffer);
// Count the number of frames encoded in the past 1 second.
const int encoded_frames_in_last_second =
show_frame ? count_frames(buffer, TICKS_PER_SEC) : 0;
@@ -633,7 +659,6 @@
level_stats->min_frame_width = AOMMIN(level_stats->min_frame_width, width);
level_stats->min_frame_height =
AOMMIN(level_stats->min_frame_height, height);
- level_stats->total_compressed_size += frame_compressed_size;
if (show_frame) level_stats->total_time_encoded = total_time_encoded;
level_stats->min_cr = AOMMIN(level_stats->min_cr, compression_ratio);
@@ -649,7 +674,8 @@
level_spec->max_tiles = AOMMAX(level_spec->max_tiles, tiles);
if (show_frame) {
- scan_past_frames(buffer, encoded_frames_in_last_second, level_spec);
+ scan_past_frames(buffer, encoded_frames_in_last_second, level_spec,
+ level_stats);
}
// Check whether target level is met.
@@ -658,8 +684,9 @@
const AV1LevelSpec *const target_level_spec =
av1_level_defs + target_seq_level_idx;
const int tier = seq_params->tier[i];
- const TARGET_LEVEL_FAIL_ID fail_id = check_level_constraints(
- target_level_spec, level_spec, level_stats, tier, is_still_picture);
+ const TARGET_LEVEL_FAIL_ID fail_id =
+ check_level_constraints(target_level_spec, level_spec, level_stats,
+ tier, is_still_picture, profile);
if (fail_id != TARGET_LEVEL_OK) {
const int target_level_major = 2 + (target_seq_level_idx >> 2);
const int target_level_minor = target_seq_level_idx & 3;
@@ -682,6 +709,7 @@
}
const int is_still_picture = seq_params->still_picture;
+ const BITSTREAM_PROFILE profile = seq_params->profile;
for (int op = 0; op < seq_params->operating_points_cnt_minus_1 + 1; ++op) {
seq_level_idx[op] = (int)SEQ_LEVEL_MAX;
const int tier = seq_params->tier[op];
@@ -690,8 +718,9 @@
const AV1LevelSpec *const level_spec = &level_info->level_spec;
for (int level = 0; level < SEQ_LEVELS; ++level) {
const AV1LevelSpec *const target_level_spec = av1_level_defs + level;
- const TARGET_LEVEL_FAIL_ID fail_id = check_level_constraints(
- target_level_spec, level_spec, level_stats, tier, is_still_picture);
+ const TARGET_LEVEL_FAIL_ID fail_id =
+ check_level_constraints(target_level_spec, level_spec, level_stats,
+ tier, is_still_picture, profile);
if (fail_id == TARGET_LEVEL_OK) {
seq_level_idx[op] = level;
break;
diff --git a/av1/encoder/level.h b/av1/encoder/level.h
index b2c1156..c4e20c8 100644
--- a/av1/encoder/level.h
+++ b/av1/encoder/level.h
@@ -37,6 +37,7 @@
typedef struct {
int64_t ts_start;
int64_t ts_end;
+ size_t encoded_size_in_bytes;
int pic_size;
int frame_header_count;
int tiles;
@@ -54,7 +55,7 @@
// Used to keep track of AV1 Level Stats. Currently unimplemented.
typedef struct {
- uint64_t total_compressed_size;
+ int max_bitrate; // In bps.
int max_tile_size;
int max_superres_tile_width;
int min_cropped_tile_width;
