diff --git a/Cargo.lock b/Cargo.lock
index 0967741..22d0ee5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -138,6 +138,12 @@ version = "0.21.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "35636a1494ede3b646cc98f74f8e62c773a38a659ebc777a2cf26b9b74171df9"
 
+[[package]]
+name = "bit_field"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc827186963e592360843fb5ba4b973e145841266c1357f7180c43526f2e5b61"
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -200,9 +206,11 @@ version = "0.1.0"
 dependencies = [
  "atrium-api",
  "atrium-xrpc-client",
+ "bytes",
  "chrono",
  "feed-rs",
  "html5ever",
+ "image",
  "reqwest",
  "tokio",
  "unicode-normalization",
@@ -214,6 +222,18 @@ version = "3.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f30e7476521f6f8af1a1c4c0b8cc94f0bee37d91763d0ca2665f299b6cd8aec"
 
+[[package]]
+name = "bytemuck"
+version = "1.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "374d28ec25809ee0e23827c2ab573d729e293f281dfe393500e7ad618baa61c6"
+
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
 [[package]]
 name = "bytes"
 version = "1.5.0"
@@ -226,6 +246,7 @@ version = "1.0.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f1174fb0b6ec23863f8b971027804a42614e347eafb0a95bf0b12cdae21fc4d0"
 dependencies = [
+ "jobserver",
  "libc",
 ]
 
@@ -263,6 +284,12 @@ dependencies = [
  "unsigned-varint",
 ]
 
+[[package]]
+name = "color_quant"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d7b894f5411737b7867f4827955924d7c254fc9f4d91a6aad6b097804b1018b"
+
 [[package]]
 name = "constant_time_eq"
 version = "0.3.0"
@@ -303,6 +330,52 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crc32fast"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b540bd8bc810d3885c6ea91e2018302f68baba2129ab3e88f32389ee9370880d"
+dependencies = [
+ "cfg-if",
+]
+
+[[package]]
+name = "crossbeam-deque"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fca89a0e215bab21874660c67903c5f143333cab1da83d041c7ded6053774751"
+dependencies = [
+ "cfg-if",
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.9.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e3681d554572a651dda4186cd47240627c3d0114d45a95f6ad27f2f22e7548d"
+dependencies = [
+ "autocfg",
+ "cfg-if",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3a430a770ebd84726f584a90ee7f020d28db52c6d02138900f22341f866d39c"
+dependencies = [
+ "cfg-if",
+]
+
+[[package]]
+name = "crunchy"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"
+
 [[package]]
 name = "crypto-common"
 version = "0.1.6"
@@ -349,6 +422,12 @@ dependencies = [
  "crypto-common",
 ]
 
+[[package]]
+name = "either"
+version = "1.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
+
 [[package]]
 name = "encoding_rs"
 version = "0.8.33"
@@ -374,12 +453,37 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "exr"
+version = "1.71.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "832a761f35ab3e6664babfbdc6cef35a4860e816ec3916dcfd0882954e98a8a8"
+dependencies = [
+ "bit_field",
+ "flume",
+ "half",
+ "lebe",
+ "miniz_oxide",
+ "rayon-core",
+ "smallvec",
+ "zune-inflate",
+]
+
 [[package]]
 name = "fastrand"
 version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "25cbce373ec4653f1a01a31e8a5e5ec0c622dc27ff9c4e6606eefef5cbbed4a5"
 
+[[package]]
+name = "fdeflate"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "64d6dafc854908ff5da46ff3f8f473c6984119a2876a383a860246dd7841a868"
+dependencies = [
+ "simd-adler32",
+]
+
 [[package]]
 name = "feed-rs"
 version = "1.3.0"
@@ -398,6 +502,25 @@ dependencies = [
  "uuid",
 ]
 
+[[package]]
+name = "flate2"
+version = "1.0.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46303f565772937ffe1d394a4fac6f411c6013172fadde9dcdb1e147a086940e"
+dependencies = [
+ "crc32fast",
+ "miniz_oxide",
+]
+
+[[package]]
+name = "flume"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "55ac459de2512911e4b674ce33cf20befaba382d05b62b008afc1c8b57cbf181"
+dependencies = [
+ "spin",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -498,12 +621,28 @@ dependencies = [
  "wasi",
 ]
 
+[[package]]
+name = "gif"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "80792593675e051cf94a4b111980da2ba60d4a83e43e0048c5693baab3977045"
+dependencies = [
+ "color_quant",
+ "weezl",
+]
+
 [[package]]
 name = "gimli"
 version = "0.28.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4271d37baee1b8c7e4b708028c57d816cf9d2434acb33a549475f78c181f6253"
 
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
 [[package]]
 name = "h2"
 version = "0.3.22"
@@ -523,6 +662,15 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "half"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02b4af3693f1b705df946e9fe5631932443781d0aabb423b62fcd4d73f6d2fd0"
+dependencies = [
+ "crunchy",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.14.3"
@@ -653,6 +801,26 @@ dependencies = [
  "unicode-normalization",
 ]
 
+[[package]]
+name = "image"
+version = "0.24.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6f3dfdbdd72063086ff443e297b61695500514b1e41095b6fb9a5ab48a70a711"
+dependencies = [
+ "bytemuck",
+ "byteorder",
+ "color_quant",
+ "exr",
+ "gif",
+ "jpeg-decoder",
+ "num-rational",
+ "num-traits",
+ "png",
+ "qoi",
+ "tiff",
+ "webp",
+]
+
 [[package]]
 name = "indexmap"
 version = "2.1.0"
@@ -675,6 +843,24 @@ version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b1a46d1a171d865aa5f83f92695765caa047a9b4cbae2cbf37dbd613a793fd4c"
 
+[[package]]
+name = "jobserver"
+version = "0.1.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8c37f63953c4c63420ed5fd3d6d398c719489b9f872b9fa683262f8edd363c7d"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "jpeg-decoder"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc0000e42512c92e31c2252315bda326620a4e034105e900c98ec492fa077b3e"
+dependencies = [
+ "rayon",
+]
+
 [[package]]
 name = "js-sys"
 version = "0.3.66"
@@ -699,12 +885,28 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
+[[package]]
+name = "lebe"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03087c2bad5e1034e8cace5926dec053fb3790248370865f5117a7d0213354c8"
+
 [[package]]
 name = "libc"
 version = "0.2.151"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "302d7ab3130588088d277783b1e2d2e10c9e9e4a16dd9050e6ec93fb3e7048f4"
 
+[[package]]
+name = "libwebp-sys"
+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3e0df0a0f9444d52aee6335cd724d21a2ee3285f646291799a72be518ec8ee3c"
+dependencies = [
+ "cc",
+ "glob",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.12"
@@ -766,6 +968,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e7810e0be55b428ada41041c41f32c9f1a42817901b4ccf45fa3d4b6561e74c7"
 dependencies = [
  "adler",
+ "simd-adler32",
 ]
 
 [[package]]
@@ -847,6 +1050,27 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e4a24736216ec316047a1fc4252e27dabb04218aa4a3f37c6e7ddbf1f9782b54"
 
+[[package]]
+name = "num-integer"
+version = "0.1.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "225d3389fb3509a24c93f5c29eb6bde2586b98d9f016636dff58d7c6f7569cd9"
+dependencies = [
+ "autocfg",
+ "num-traits",
+]
+
+[[package]]
+name = "num-rational"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0638a1c9d0a3c0914158145bc76cff373a75a627e6ecbfb71cbe6f453a5a19b0"
+dependencies = [
+ "autocfg",
+ "num-integer",
+ "num-traits",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.17"
@@ -1010,6 +1234,19 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "69d3587f8a9e599cc7ec2c00e331f71c4e69a5f9a4b8a6efd5b07466b9736f9a"
 
+[[package]]
+name = "png"
+version = "0.17.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd75bf2d8dd3702b9707cdbc56a5b9ef42cec752eb8b3bafc01234558442aa64"
+dependencies = [
+ "bitflags 1.3.2",
+ "crc32fast",
+ "fdeflate",
+ "flate2",
+ "miniz_oxide",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.17"
@@ -1065,6 +1302,15 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "qoi"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f6d64c71eb498fe9eae14ce4ec935c555749aef511cca85b5568910d6e48001"
+dependencies = [
+ "bytemuck",
+]
+
 [[package]]
 name = "quick-xml"
 version = "0.27.1"
@@ -1114,6 +1360,26 @@ dependencies = [
  "getrandom",
 ]
 
+[[package]]
+name = "rayon"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c27db03db7734835b3f53954b534c91069375ce6ccaa2e065441e07d9b6cdb1"
+dependencies = [
+ "either",
+ "rayon-core",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5ce3fb6ad83f861aac485e76e1985cd109d9a3713802152be56c3b1f0e0658ed"
+dependencies = [
+ "crossbeam-deque",
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.4.1"
@@ -1355,6 +1621,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "simd-adler32"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d66dc143e6b11c1eddc06d5c423cfc97062865baf299914ab64caa38182078fe"
+
 [[package]]
 name = "siphasher"
 version = "0.3.11"
@@ -1386,6 +1658,15 @@ dependencies = [
  "windows-sys 0.48.0",
 ]
 
+[[package]]
+name = "spin"
+version = "0.9.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"
+dependencies = [
+ "lock_api",
+]
+
 [[package]]
 name = "string_cache"
 version = "0.8.7"
@@ -1511,6 +1792,17 @@ dependencies = [
  "syn 2.0.42",
 ]
 
+[[package]]
+name = "tiff"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d172b0f4d3fba17ba89811858b9d3d97f928aece846475bbda076ca46736211"
+dependencies = [
+ "flate2",
+ "jpeg-decoder",
+ "weezl",
+]
+
 [[package]]
 name = "tinyvec"
 version = "1.6.0"
@@ -1788,6 +2080,21 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "webp"
+version = "0.2.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4bb5d8e7814e92297b0e1c773ce43d290bef6c17452dafd9fc49e5edb5beba71"
+dependencies = [
+ "libwebp-sys",
+]
+
+[[package]]
+name = "weezl"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9193164d4de03a926d909d3bc7c30543cecb35400c02114792c2cae20d5e2dbb"
+
 [[package]]
 name = "windows-core"
 version = "0.51.1"
@@ -1938,3 +2245,12 @@ dependencies = [
  "cfg-if",
  "windows-sys 0.48.0",
 ]
+
+[[package]]
+name = "zune-inflate"
+version = "0.2.54"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73ab332fe2f6680068f3582b16a24f90ad7096d5d39b974d1c0aff0125116f02"
+dependencies = [
+ "simd-adler32",
+]
diff --git a/Cargo.toml b/Cargo.toml
index f12e567..15cdf0a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+bytes = { version = "1" }
 reqwest = { version = "0.11", features = [] }
 tokio = { version = "1", features = ["full"] }
 feed-rs = { version = "1" }
@@ -12,3 +13,4 @@ atrium-xrpc-client = { version = "0.2" }
 unicode-normalization = { version = "0.1" }
 chrono = { version = "0.4" }
 html5ever = { version = "0.26" }
+image = { version = "0.24", features = ["webp-encoder"] }
diff --git a/src/main.rs b/src/main.rs
index 8b8e834..e10d7ed 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,7 +11,12 @@ use atrium_api::{
     xrpc::XrpcClient,
 };
 use atrium_xrpc_client::reqwest::ReqwestClient;
+use bytes::Bytes;
 use feed_rs::model::{Entry, Feed};
+use image::{
+    codecs::webp::{WebPEncoder, WebPQuality},
+    ColorType, ImageEncoder,
+};
 use unicode_normalization::UnicodeNormalization;
 
 use bluesky_rss_bot::ogp::{get_ogp, Ogp};
@@ -100,6 +105,39 @@ async fn get_ogp_from_url(url: &str) -> Result<Ogp, Box<dyn std::error::Error>>
     Ok(get_ogp(content))
 }
 
+fn adjust_size_of_image(
+    mut blob: Bytes,
+    max_size: usize,
+) -> Result<Bytes, Box<dyn std::error::Error>> {
+    let image = image::load_from_memory(&blob)?.into_rgba8();
+
+    // try to re-encode the image to lossless WebP in any ways.
+    blob = {
+        let mut out = std::io::BufWriter::new(Vec::new());
+        WebPEncoder::new_with_quality(&mut out, WebPQuality::lossless()).write_image(
+            &image,
+            image.width(),
+            image.height(),
+            ColorType::Rgba8,
+        )?;
+        Bytes::from(out.into_inner()?)
+    };
+
+    let mut quality = 100;
+    while blob.len() > max_size {
+        let mut out = std::io::BufWriter::new(Vec::new());
+        WebPEncoder::new_with_quality(&mut out, WebPQuality::lossy(quality)).write_image(
+            &image,
+            image.width(),
+            image.height(),
+            ColorType::Rgba8,
+        )?;
+        blob = Bytes::from(out.into_inner()?);
+        quality -= 1;
+    }
+    Ok(blob)
+}
+
 async fn create_embed_ogp<S: SessionStore + Send + Sync, T: XrpcClient + Send + Sync>(
     agent: &AtpAgent<S, T>,
     source_url: &str,
@@ -108,7 +146,9 @@ async fn create_embed_ogp<S: SessionStore + Send + Sync, T: XrpcClient + Send +
     let og_image = ogp
         .og_image
         .ok_or_else(|| format!("og:image is not found in {:?}", source_url))?;
-    let blob = reqwest::get(og_image).await?.bytes().await?;
+    let max_blob_size = 1_000_000; // 1MB (not 1MiB)
+    let blob = adjust_size_of_image(reqwest::get(og_image).await?.bytes().await?, max_blob_size)?;
+
     let uploaded_blob = agent
         .api
         .com