Fix overflow caused by large timestamps
- Save the initial user-specified timestamp and rebase all further
timestamps by this value. This makes libaom internal timestamps to
always start from zero, regardless of the user's timestamps.
- Calculate reduced timestamp conversion ratio and use it to convert
user's timestamps to libaom internal timestamps and back. The effect
of this is that integer overflow due to multiplication doesn't
happen for a much longer time.
- Turned on TestAv1Rollover in TimestampTest to verify the
issue is fixed
BUG=aomedia:2053
Change-Id: I50817acf190027b71702303501439daa9a62505c
diff --git a/av1/av1_cx_iface.c b/av1/av1_cx_iface.c
index 398d672..e800287 100644
--- a/av1/av1_cx_iface.c
+++ b/av1/av1_cx_iface.c
@@ -263,6 +263,9 @@
aom_codec_priv_t base;
aom_codec_enc_cfg_t cfg;
struct av1_extracfg extra_cfg;
+ aom_rational64_t timestamp_ratio;
+ aom_codec_pts_t pts_offset;
+ unsigned char pts_offset_initialized;
AV1EncoderConfig oxcf;
AV1_COMP *cpi;
unsigned char *cx_data;
@@ -280,6 +283,23 @@
BufferPool *buffer_pool;
};
+static INLINE int gcd(int64_t a, int b) {
+ int remainder; // remainder
+ while (b > 0) {
+ remainder = (int)(a % b);
+ a = b;
+ b = remainder;
+ }
+
+ return (int)a;
+}
+
+static INLINE void reduce_ratio(aom_rational64_t *ratio) {
+ const int denom = gcd(ratio->num, ratio->den);
+ ratio->num /= denom;
+ ratio->den /= denom;
+}
+
static aom_codec_err_t update_error_state(
aom_codec_alg_priv_t *ctx, const struct aom_internal_error_info *error) {
const aom_codec_err_t res = error->error_code;
@@ -1618,6 +1638,11 @@
res = validate_config(priv, &priv->cfg, &priv->extra_cfg);
if (res == AOM_CODEC_OK) {
+ priv->timestamp_ratio.den = priv->cfg.g_timebase.den;
+ priv->timestamp_ratio.num =
+ (int64_t)priv->cfg.g_timebase.num * TICKS_PER_SEC;
+ reduce_ratio(&priv->timestamp_ratio);
+
set_encoder_config(&priv->oxcf, &priv->cfg, &priv->extra_cfg);
priv->oxcf.use_highbitdepth =
(ctx->init_flags & AOM_CODEC_USE_HIGHBITDEPTH) ? 1 : 0;
@@ -1665,7 +1690,8 @@
const size_t kMinCompressedSize = 8192;
volatile aom_codec_err_t res = AOM_CODEC_OK;
AV1_COMP *const cpi = ctx->cpi;
- const aom_rational_t *const timebase = &ctx->cfg.g_timebase;
+ const aom_rational64_t *const timestamp_ratio = &ctx->timestamp_ratio;
+ volatile aom_codec_pts_t ptsvol = pts;
if (cpi == NULL) return AOM_CODEC_INVALID_PARAM;
@@ -1692,6 +1718,12 @@
av1_change_config(ctx->cpi, &ctx->oxcf);
}
+ if (!ctx->pts_offset_initialized) {
+ ctx->pts_offset = ptsvol;
+ ctx->pts_offset_initialized = 1;
+ }
+ ptsvol -= ctx->pts_offset;
+
aom_codec_pkt_list_init(&ctx->pkt_list);
volatile aom_enc_frame_flags_t flags = enc_flags;
@@ -1722,9 +1754,9 @@
}
if (res == AOM_CODEC_OK) {
- int64_t dst_time_stamp = timebase_units_to_ticks(timebase, pts);
+ int64_t dst_time_stamp = timebase_units_to_ticks(timestamp_ratio, ptsvol);
int64_t dst_end_time_stamp =
- timebase_units_to_ticks(timebase, pts + duration);
+ timebase_units_to_ticks(timestamp_ratio, ptsvol + duration);
// Set up internal flags
if (ctx->base.init_flags & AOM_CODEC_USE_PSNR) cpi->b_calculate_psnr = 1;
@@ -1773,7 +1805,7 @@
!is_frame_visible &&
-1 != av1_get_compressed_data(cpi, &lib_flags, &frame_size, cx_data,
&dst_time_stamp, &dst_end_time_stamp,
- !img, timebase)) {
+ !img, timestamp_ratio)) {
cpi->seq_params_locked = 1;
if (frame_size) {
if (ctx->pending_cx_data == 0) ctx->pending_cx_data = cx_data;
@@ -1868,7 +1900,9 @@
pkt.data.frame.partition_id = -1;
pkt.data.frame.vis_frame_size = frame_size;
- pkt.data.frame.pts = ticks_to_timebase_units(timebase, dst_time_stamp);
+ pkt.data.frame.pts =
+ ticks_to_timebase_units(timestamp_ratio, dst_time_stamp) +
+ ctx->pts_offset;
pkt.data.frame.flags = get_frame_pkt_flags(cpi, lib_flags);
if (has_fwd_keyframe) {
// If one of the invisible frames in the packet is a keyframe, set
@@ -1876,7 +1910,7 @@
pkt.data.frame.flags |= AOM_FRAME_IS_DELAYED_RANDOM_ACCESS_POINT;
}
pkt.data.frame.duration = (uint32_t)ticks_to_timebase_units(
- timebase, dst_end_time_stamp - dst_time_stamp);
+ timestamp_ratio, dst_end_time_stamp - dst_time_stamp);
aom_codec_pkt_list_add(&ctx->pkt_list.head, &pkt);
diff --git a/av1/encoder/encode_strategy.c b/av1/encoder/encode_strategy.c
index e9d6ee7..20687f3 100644
--- a/av1/encoder/encode_strategy.c
+++ b/av1/encoder/encode_strategy.c
@@ -947,7 +947,8 @@
int av1_encode_strategy(AV1_COMP *const cpi, size_t *const size,
uint8_t *const dest, unsigned int *frame_flags,
int64_t *const time_stamp, int64_t *const time_end,
- const aom_rational_t *const timebase, int flush) {
+ const aom_rational64_t *const timestamp_ratio,
+ int flush) {
const AV1EncoderConfig *const oxcf = &cpi->oxcf;
AV1_COMMON *const cm = &cpi->common;
@@ -1027,7 +1028,7 @@
cm->seq_params.film_grain_params_present;
}
// only one operating point supported now
- const int64_t pts64 = ticks_to_timebase_units(timebase, *time_stamp);
+ const int64_t pts64 = ticks_to_timebase_units(timestamp_ratio, *time_stamp);
if (pts64 < 0 || pts64 > UINT32_MAX) return AOM_CODEC_ERROR;
cpi->common.frame_presentation_time = (uint32_t)pts64;
}
diff --git a/av1/encoder/encode_strategy.h b/av1/encoder/encode_strategy.h
index 6830e44..7601547 100644
--- a/av1/encoder/encode_strategy.h
+++ b/av1/encoder/encode_strategy.h
@@ -29,7 +29,8 @@
int av1_encode_strategy(AV1_COMP *const cpi, size_t *const size,
uint8_t *const dest, unsigned int *frame_flags,
int64_t *const time_stamp, int64_t *const time_end,
- const aom_rational_t *const timebase, int flush);
+ const aom_rational64_t *const timestamp_ratio,
+ int flush);
// Set individual buffer update flags based on frame reference type.
// force_refresh_all is used when we have a KEY_FRAME or S_FRAME. It forces all
diff --git a/av1/encoder/encoder.c b/av1/encoder/encoder.c
index e33b36b..fda398c 100644
--- a/av1/encoder/encoder.c
+++ b/av1/encoder/encoder.c
@@ -5408,7 +5408,7 @@
int av1_get_compressed_data(AV1_COMP *cpi, unsigned int *frame_flags,
size_t *size, uint8_t *dest, int64_t *time_stamp,
int64_t *time_end, int flush,
- const aom_rational_t *timebase) {
+ const aom_rational64_t *timestamp_ratio) {
const AV1EncoderConfig *const oxcf = &cpi->oxcf;
AV1_COMMON *const cm = &cpi->common;
@@ -5444,8 +5444,9 @@
if (assign_cur_frame_new_fb(cm) == NULL) return AOM_CODEC_ERROR;
- const int result = av1_encode_strategy(cpi, size, dest, frame_flags,
- time_stamp, time_end, timebase, flush);
+ const int result =
+ av1_encode_strategy(cpi, size, dest, frame_flags, time_stamp, time_end,
+ timestamp_ratio, flush);
if (result != AOM_CODEC_OK && result != -1) {
return AOM_CODEC_ERROR;
} else if (result == -1) {
@@ -5455,7 +5456,7 @@
#if CONFIG_INTERNAL_STATS
aom_usec_timer_mark(&cmptimer);
cpi->time_compress_data += aom_usec_timer_elapsed(&cmptimer);
-#endif
+#endif // CONFIG_INTERNAL_STATS
if (cpi->b_calculate_psnr) {
if (cm->show_existing_frame || (oxcf->pass != 1 && cm->show_frame)) {
generate_psnr_packet(cpi);
diff --git a/av1/encoder/encoder.h b/av1/encoder/encoder.h
index edb9507..865d2b1 100644
--- a/av1/encoder/encoder.h
+++ b/av1/encoder/encoder.h
@@ -56,6 +56,15 @@
extern "C" {
#endif
+/*!\brief Rational Number with an int64 numerator
+ *
+ * This structure holds a fractional value.
+ */
+typedef struct aom_rational64 {
+ int64_t num; /**< fraction numerator */
+ int den; /**< fraction denominator */
+} aom_rational64_t; /**< alias for struct aom_rational */
+
typedef struct {
int nmv_vec_cost[MV_JOINTS];
int nmv_costs[2][MV_VALS];
@@ -1061,7 +1070,7 @@
int av1_get_compressed_data(AV1_COMP *cpi, unsigned int *frame_flags,
size_t *size, uint8_t *dest, int64_t *time_stamp,
int64_t *time_end, int flush,
- const aom_rational_t *timebase);
+ const aom_rational64_t *timebase);
int av1_encode(AV1_COMP *const cpi, uint8_t *const dest,
const EncodeFrameInput *const frame_input,
@@ -1100,15 +1109,16 @@
// av1 uses 10,000,000 ticks/second as time stamp
#define TICKS_PER_SEC 10000000LL
-static INLINE int64_t timebase_units_to_ticks(const aom_rational_t *timebase,
- int64_t n) {
- return n * TICKS_PER_SEC * timebase->num / timebase->den;
+static INLINE int64_t
+timebase_units_to_ticks(const aom_rational64_t *timestamp_ratio, int64_t n) {
+ return n * timestamp_ratio->num / timestamp_ratio->den;
}
-static INLINE int64_t ticks_to_timebase_units(const aom_rational_t *timebase,
- int64_t n) {
- const int64_t round = TICKS_PER_SEC * timebase->num / 2 - 1;
- return (n * timebase->den + round) / timebase->num / TICKS_PER_SEC;
+static INLINE int64_t
+ticks_to_timebase_units(const aom_rational64_t *timestamp_ratio, int64_t n) {
+ int64_t round = timestamp_ratio->num / 2;
+ if (round > 0) --round;
+ return (n * timestamp_ratio->den + round) / timestamp_ratio->num;
}
static INLINE int frame_is_kf_gf_arf(const AV1_COMP *cpi) {
diff --git a/test/time_stamp_test.cc b/test/time_stamp_test.cc
index 0ce47d5..2c23785 100644
--- a/test/time_stamp_test.cc
+++ b/test/time_stamp_test.cc
@@ -92,7 +92,7 @@
ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
}
-TEST_P(TimestampTest, DISABLED_TestAv1Rollover) {
+TEST_P(TimestampTest, TestAv1Rollover) {
DummyTimebaseVideoSource video(1, 1000);
video.set_starting_pts(922337170351ll);
ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
