From 988838cf4f1e6e217226f9520303a948b2294ae2 Mon Sep 17 00:00:00 2001
From: Zhao Zhili <zhilizhao@tencent.com>
Date: Fri, 29 Jul 2022 12:43:09 +0800
Subject: [PATCH] avformat/flvdec: make key frame timestamps more accurate

There was an implicit cast from double to int64_t in time unit of
second.
---
 libavformat/flvdec.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/libavformat/flvdec.c b/libavformat/flvdec.c
index 8dba92661b..10f0ea7736 100644
--- a/libavformat/flvdec.c
+++ b/libavformat/flvdec.c
@@ -146,9 +146,9 @@ static void add_keyframes_index(AVFormatContext *s)
     if (ffstream(stream)->nb_index_entries == 0) {
         for (i = 0; i < flv->keyframe_count; i++) {
             av_log(s, AV_LOG_TRACE, "keyframe filepositions = %"PRId64" times = %"PRId64"\n",
-                   flv->keyframe_filepositions[i], flv->keyframe_times[i] * 1000);
+                   flv->keyframe_filepositions[i], flv->keyframe_times[i]);
             av_add_index_entry(stream, flv->keyframe_filepositions[i],
-                flv->keyframe_times[i] * 1000, 0, 0, AVINDEX_KEYFRAME);
+                flv->keyframe_times[i], 0, 0, AVINDEX_KEYFRAME);
         }
     } else
         av_log(s, AV_LOG_WARNING, "Skipping duplicate index\n");
@@ -428,6 +428,7 @@ static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, int64_t m
            amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
         int64_t **current_array;
         unsigned int arraylen;
+        int factor;
 
         // Expect array object in context
         if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)
@@ -440,10 +441,12 @@ static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, int64_t m
         if       (!strcmp(KEYFRAMES_TIMESTAMP_TAG , str_val) && !times) {
             current_array = &times;
             timeslen      = arraylen;
+            factor = 1000;
         } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) &&
                    !filepositions) {
             current_array = &filepositions;
             fileposlen    = arraylen;
+            factor = 1;
         } else
             // unexpected metatag inside keyframes, will not use such
             // metadata for indexing
@@ -458,11 +461,9 @@ static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, int64_t m
             double d;
             if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)
                 goto invalid;
-            d = av_int2double(avio_rb64(ioc));
+            d = av_int2double(avio_rb64(ioc)) * factor;
             if (isnan(d) || d < INT64_MIN || d > INT64_MAX)
                 goto invalid;
-            if (current_array == &times && (d <= INT64_MIN / 1000 || d >= INT64_MAX / 1000))
-                goto invalid;
             if (avio_feof(ioc))
                 goto invalid;
             current_array[0][i] = d;
@@ -478,7 +479,7 @@ static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, int64_t m
     if (timeslen == fileposlen && fileposlen>1 && max_pos <= filepositions[0]) {
         for (i = 0; i < FFMIN(2,fileposlen); i++) {
             flv->validate_index[i].pos = filepositions[i];
-            flv->validate_index[i].dts = times[i] * 1000;
+            flv->validate_index[i].dts = times[i];
             flv->validate_count        = i + 1;
         }
         flv->keyframe_times = times;