| // Copyright 2018 The Wuffs Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // ---------------- |
| |
| // This program exercises the Rust GIF decoder at |
| // https://github.com/PistonDevelopers/image-gif |
| // |
| // Wuffs' C code doesn't depend on Rust per se, but this program gives some |
| // performance data for specific Rust GIF implementations. The equivalent Wuffs |
| // benchmarks (on the same test image) are run via: |
| // |
| // wuffs bench -mimic -focus=wuffs_gif_decode_1000k,mimic_gif_decode_1000k std/gif |
| // |
| // The "1000k" is because the test image (harvesters.gif) has approximately 1 |
| // million pixels. |
| // |
| // The Wuffs benchmark reports megabytes per second. This program reports |
| // megapixels per second. The two concepts should be equivalent, since GIF |
| // images' pixel data are always 1 byte per pixel indices into a color palette. |
| // |
| // To run this program, do "cargo run --release" from the parent directory (the |
| // directory containing the Cargo.toml file). |
| |
| // TODO: unify this program, bench-rust-gif-dot-rs, with bench-rust-gif, the |
| // other Rust GIF benchmark program. They are two separate programs because |
| // both libraries want to be named "gif", and the cargo package manager cannot |
| // handle duplicate names (https://github.com/rust-lang/cargo/issues/1311). |
| |
| extern crate gif; |
| |
| use std::time::Instant; |
| |
| // These constants are hard-coded to the harvesters.gif test image. |
| const WIDTH: usize = 1165; |
| const HEIGHT: usize = 859; |
| const BYTES_PER_PIXEL: usize = 1; // Palette index. |
| const NUM_BYTES: usize = WIDTH * HEIGHT * BYTES_PER_PIXEL; |
| const FIRST_PIXEL: u8 = 0; // Top left pixel's palette index is 0x00. |
| const LAST_PIXEL: u8 = 1; // Bottom right pixel's palette index is 0x01. |
| |
| fn main() { |
| let mut dst = [0; NUM_BYTES]; |
| let src = include_bytes!("../../../test/data/harvesters.gif"); |
| |
| let start = Instant::now(); |
| |
| const REPS: u32 = 50; |
| for _ in 0..REPS { |
| decode(&mut dst[..], src); |
| } |
| |
| let elapsed = start.elapsed(); |
| let elapsed_nanos = elapsed.as_secs() * 1_000_000_000 + (elapsed.subsec_nanos() as u64); |
| |
| let total_pixels: u64 = ((WIDTH * HEIGHT) as u64) * (REPS as u64); |
| let kp_per_s: u64 = total_pixels * 1_000_000 / elapsed_nanos; |
| |
| print!( |
| "gif {:3}.{:03} megapixels/second github.com/PistonDevelopers/image-gif\n", |
| kp_per_s / 1_000, |
| kp_per_s % 1_000 |
| ); |
| } |
| |
| fn decode(dst: &mut [u8], src: &[u8]) { |
| // Set up the hard-coded sanity check, executed below. |
| dst[0] = 0xFE; |
| dst[NUM_BYTES - 1] = 0xFE; |
| |
| let mut reader = gif::Decoder::new(src).read_info().unwrap(); |
| reader.next_frame_info().unwrap().unwrap(); |
| |
| if reader.buffer_size() != NUM_BYTES { |
| panic!("wrong num_bytes") |
| } |
| |
| reader.read_into_buffer(dst).unwrap(); |
| |
| // A hard-coded sanity check that we decoded the pixel data correctly. |
| if (dst[0] != FIRST_PIXEL) || (dst[NUM_BYTES - 1] != LAST_PIXEL) { |
| panic!("wrong dst pixels") |
| } |
| } |