doc/README.md

@@ -138,14 +138,21 @@ Parameters:
  - `feedback`: Feedback, 0..1, default 0
  - `xfade_samp`: Crossfade samples (int), 0..5000, default 1250
 
+## `wildnoise/noise split index seed repeat_bytes`
+
+Inject random noise on the image.
+
+the `wildnoise` version gives a harder version than `noise`.
+
+Parameters:
+ - `seed`, Random seed
+ - `repeat_bytes`, Amount of bytes to preload with random data and repeat
+    throughout the image slice
+
 ## TODO `echo split index delay`
 
 Run an echo filter on the given loaded file.
 
-## TODO `noise split index seed`
-
-Inject white noise on the image.
-
 ## `quicksave`
 
 Save the file on the same directory of the file specified by `load`, but

examples/noise.scri

@@ -0,0 +1,5 @@
+load :0;
+noise 5 1 3981 10000;
+wildnoise 5 2 3982 0;
+noise 5 3 3982 5;
+quicksave;

src/custom.zig

@@ -0,0 +1,96 @@
+// Custom plugins
+const std = @import("std");
+const lv2 = @import("lv2_helpers.zig");
+const plugins = @import("plugin.zig");
+
+const c = lv2.c;
+
+const RunBuffers = plugins.RunBuffers;
+
+pub const RandomNoise = struct {
+    r: std.rand.DefaultPrng,
+    rand_buf: ?[]f32,
+    cnt: usize = 0,
+
+    pub fn init(
+        allocator: *std.mem.Allocator,
+        params: *plugins.ParamMap,
+    ) !RandomNoise {
+        const seed = @floatToInt(u64, params.get("seed").?.value);
+        const fillbytes = @floatToInt(usize, params.get("fill_bytes").?.value);
+
+        var r = std.rand.DefaultPrng.init(seed);
+
+        if (fillbytes > 0) {
+            var rand_buf = try allocator.alloc(f32, fillbytes);
+
+            for (rand_buf) |_, idx| {
+                rand_buf[idx] = r.random.float(f32);
+            }
+
+            return RandomNoise{
+                .r = r,
+                .rand_buf = rand_buf,
+            };
+        } else {
+            return RandomNoise{
+                .r = r,
+                .rand_buf = null,
+            };
+        }
+    }
+
+    pub fn run(self: *RandomNoise, bufs: *RunBuffers) void {
+        if (self.rand_buf) |rand_buf| {
+            if (self.cnt >= rand_buf.len) self.cnt = 0;
+            bufs.out[0] = rand_buf[self.cnt];
+            self.cnt += 1;
+        } else {
+            bufs.out[0] = self.r.random.float(f32);
+        }
+    }
+};
+
+pub const WildNoise = struct {
+    r: std.rand.DefaultPrng,
+    rand_buf: ?[]f32,
+    cnt: usize = 0,
+
+    pub fn init(
+        allocator: *std.mem.Allocator,
+        params: *plugins.ParamMap,
+    ) !WildNoise {
+        const seed = @floatToInt(u64, params.get("seed").?.value);
+        const fillbytes = @floatToInt(usize, params.get("fill_bytes").?.value);
+
+        var r = std.rand.DefaultPrng.init(seed);
+
+        if (fillbytes > 0) {
+            var rand_buf = try allocator.alloc(f32, fillbytes);
+
+            for (rand_buf) |_, idx| {
+                rand_buf[idx] = @intToFloat(f32, r.random.int(u1));
+            }
+
+            return WildNoise{
+                .r = r,
+                .rand_buf = rand_buf,
+            };
+        } else {
+            return WildNoise{
+                .r = r,
+                .rand_buf = null,
+            };
+        }
+    }
+
+    pub fn run(self: *WildNoise, bufs: *RunBuffers) void {
+        if (self.rand_buf) |rand_buf| {
+            if (self.cnt >= rand_buf.len) self.cnt = 0;
+            bufs.out[0] = rand_buf[self.cnt];
+            self.cnt += 1;
+        } else {
+            bufs.out[0] = @intToFloat(f32, self.r.random.int(u1));
+        }
+    }
+};

src/image.zig

@@ -62,7 +62,7 @@ fn getEndPos(path: []const u8) !usize {
 
 fn temporaryName(allocator: *std.mem.Allocator) ![]u8 {
     const template_start = "/temp/temp_";
-    const template = "/tmp/temp_XXXXXX";
+    const template = "/tmp/temp_XXXXXXXX";
     var nam = try allocator.alloc(u8, template.len);
     std.mem.copy(u8, nam, template);
 
@@ -292,15 +292,18 @@ pub const Image = struct {
         var i: usize = seek_pos.start;
         std.debug.warn("\tseek pos start: {} end: {}\n", seek_pos.start, seek_pos.end);
 
+        var inbuf = rctx.buffers.in;
+        var outbuf = rctx.buffers.out;
+
         while (i <= seek_pos.end) : (i += 1) {
-            const read_bytes = c.sf_readf_float(self.sndfile, rctx.in_buf.ptr, 1);
+            const read_bytes = c.sf_readf_float(self.sndfile, inbuf.ptr, 1);
             if (read_bytes == 0) {
                 std.debug.warn("WARN! reached EOF at idx={}\n", i);
                 break;
             }
 
             lv2.lilv_instance_run(rctx.instance, 1);
-            try swrite(out_file, rctx.out_buf.ptr, 1);
+            try swrite(out_file, outbuf.ptr, 1);
         }
 
         _ = c.sf_seek(self.sndfile, @intCast(i64, seek_pos.end), c.SEEK_SET);
@@ -326,4 +329,85 @@ pub const Image = struct {
         std.debug.warn("saved to '{}'\n", out_path);
         try std.fs.copyFile(self.curpath, out_path);
     }
+
+    pub fn runCustomPlugin(
+        self: *Image,
+        comptime Plugin: type,
+        position: plugins.Position,
+        params: *plugins.ParamMap,
+    ) !void {
+        var plugin = try Plugin.init(self.allocator, params);
+
+        // the code here is a copypaste of runPlugin() without the specific
+        // lilv things.
+        var tmpnam = try temporaryName(self.allocator);
+        std.debug.warn("\trunning CUSTOM plugin from '{}' to '{}'\n", self.curpath, tmpnam);
+
+        var out_fmt = mkSfInfo();
+        var out_file = try sopen(self.allocator, tmpnam, c.SFM_WRITE, &out_fmt);
+
+        var bufs = try plugins.RunBuffers.init(self.allocator);
+        defer bufs.deinit();
+
+        const file_end = try getEndPos(self.curpath);
+        const seek_pos = position.seekPos(file_end);
+        std.debug.warn("\tstart {} end {}\n", seek_pos.start, seek_pos.end);
+
+        // make sure we start from 0
+        _ = c.sf_seek(self.sndfile, 0, c.SEEK_SET);
+
+        // there are four main stages:
+        // - the bmp header copy
+        // - pre-plugin
+        // - CUSTOM plugin
+        // - post-plugin
+
+        var file_copy_buf = try self.allocator.alloc(f32, BufferSize);
+        defer self.allocator.free(file_copy_buf);
+
+        // pre-plugin copy, merged with bmp header copy
+        try self.copyBytes(
+            out_file,
+            file_copy_buf,
+            usize(0),
+            seek_pos.start + @mod(seek_pos.start, BufferSize),
+        );
+
+        _ = c.sf_seek(self.sndfile, @intCast(i64, seek_pos.start), c.SEEK_SET);
+
+        var i: usize = seek_pos.start;
+        std.debug.warn("\tseek pos start: {} end: {}\n", seek_pos.start, seek_pos.end);
+
+        var inbuf = bufs.in;
+        var outbuf = bufs.out;
+
+        while (i <= seek_pos.end) : (i += 1) {
+            const read_bytes = c.sf_readf_float(self.sndfile, bufs.in.ptr, 1);
+            if (read_bytes == 0) {
+                std.debug.warn("WARN! reached EOF at idx={}\n", i);
+                break;
+            }
+
+            plugin.run(&bufs);
+            try swrite(out_file, bufs.out.ptr, 1);
+        }
+
+        _ = c.sf_seek(self.sndfile, @intCast(i64, seek_pos.end), c.SEEK_SET);
+
+        // post-plugin copy
+        try self.copyBytes(
+            out_file,
+            file_copy_buf,
+            seek_pos.end + 1,
+            file_end + @mod(file_end, BufferSize),
+        );
+
+        c.sf_write_sync(out_file);
+        _ = c.sf_close(out_file);
+        _ = c.sf_close(self.sndfile);
+
+        // reopen the file as SFM_READ so we can run plugin chains etc
+        self.sndfile = try sopen(self.allocator, tmpnam, c.SFM_READ, &out_fmt);
+        self.curpath = tmpnam;
+    }
 };

src/lang.zig

@@ -26,6 +26,8 @@ pub const CommandType = enum {
     Delay,
     Vinyl,
     RevDelay,
+    Noise,
+    WildNoise,
 };
 
 pub const Command = struct {
@@ -106,6 +108,16 @@ pub const Command = struct {
             .value = val,
         });
     }
+
+    pub fn appendParamMap(
+        self: *Command,
+        map: *plugin.ParamMap,
+        symbol: []const u8,
+    ) !void {
+        var val = try self.floatArgAt(self.cur_idx);
+        self.cur_idx += 1;
+        _ = try map.put(symbol, val);
+    }
 };
 
 pub const CommandList = std.ArrayList(*Command);
@@ -143,6 +155,10 @@ pub const Lang = struct {
         _ = try self.keywords.put("delay", .Delay);
         _ = try self.keywords.put("vinyl", .Vinyl);
         _ = try self.keywords.put("revdelay", .RevDelay);
+
+        // custom implementations (not lv2)
+        _ = try self.keywords.put("noise", .Noise);
+        _ = try self.keywords.put("wildnoise", .WildNoise);
     }
 
     pub fn parse(self: *Lang, data: []const u8) !CommandList {

src/plugin.zig

@@ -16,6 +16,7 @@ pub const Param = struct {
 
 /// List of parameters to be set to control ports.
 pub const ParamList = std.ArrayList(Param);
+pub const ParamMap = std.AutoHashMap([]const u8, f32);
 
 /// Represents an absolute position in the image.
 pub const SeekPos = struct {
@@ -57,10 +58,36 @@ pub const Context = struct {
     }
 };
 
+/// Specific run context for non-plugins.
+pub const RunBuffers = struct {
+    allocator: *std.mem.Allocator,
+
+    in: []f32,
+    out: []f32,
+
+    pub fn init(allocator: *std.mem.Allocator) !RunBuffers {
+        // we allocate []f32 with size 2 to account for stereo plugins, however
+        // we only use &in_buf[0] and &out_buf[0], and don't use the
+        // (supposedly) right side of neither input or output.
+        var in_buf = try allocator.alloc(f32, 2);
+        std.mem.secureZero(f32, in_buf);
+
+        return RunBuffers{
+            .allocator = allocator,
+            .in = in_buf,
+            .out = try allocator.alloc(f32, 2),
+        };
+    }
+
+    pub fn deinit(self: *RunBuffers) void {
+        self.allocator.free(self.in);
+        self.allocator.free(self.out);
+    }
+};
+
 /// Represents the specific run context of plugin instantation.
 pub const RunContext = struct {
-    in_buf: []f32,
-    out_buf: []f32,
+    buffers: RunBuffers,
     instance: *c.LilvInstance,
 
     pub fn init(
@@ -79,20 +106,23 @@ pub const RunContext = struct {
         std.mem.secureZero(f32, in_buf);
 
         return RunContext{
-            .in_buf = in_buf,
-            .out_buf = try allocator.alloc(f32, 2),
+            .buffers = try RunBuffers.init(allocator),
             .instance = instance.?,
         };
     }
 
     pub fn deinit(self: *RunContext) void {
         c.lilv_instance_free(self.instance);
+        self.buffers.deinit();
     }
 
     pub fn connectPorts(self: *RunContext, ports: []*lv2.Port) void {
         var i: usize = 0;
         var o: usize = 0;
 
+        var in_buf = self.buffers.in;
+        var out_buf = self.buffers.out;
+
         for (ports) |port, p_idx| {
             var p = @intCast(u32, p_idx);
 
@@ -100,10 +130,10 @@ pub const RunContext = struct {
                 .Control => lv2.lilv_instance_connect_port(self.instance, p, &port.value),
                 .Audio => blk: {
                     if (port.is_input) {
-                        lv2.lilv_instance_connect_port(self.instance, p, &self.in_buf[i]);
+                        lv2.lilv_instance_connect_port(self.instance, p, &in_buf[i]);
                         i += 1;
                     } else {
-                        lv2.lilv_instance_connect_port(self.instance, p, &self.out_buf[o]);
+                        lv2.lilv_instance_connect_port(self.instance, p, &out_buf[o]);
                         o += 1;
                     }
                 },

src/runner.zig

@@ -2,9 +2,11 @@ const std = @import("std");
 const lang = @import("lang.zig");
 const images = @import("image.zig");
 const plugin = @import("plugin.zig");
+const custom = @import("custom.zig");
 
 const Position = plugin.Position;
 const ParamList = plugin.ParamList;
+const ParamMap = plugin.ParamMap;
 
 const Image = images.Image;
 
@@ -245,10 +247,23 @@ pub const Runner = struct {
         try image.runPlugin("http://plugin.org.uk/swh-plugins/revdelay", pos, params);
     }
 
+    fn noiseCmd(self: *Runner, pos: Position, map: *ParamMap) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.RandomNoise, pos, map);
+    }
+
+    fn wildNoiseCmd(self: *Runner, pos: Position, map: *ParamMap) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.WildNoise, pos, map);
+    }
+
     fn runCommand(self: *Runner, cmd: *lang.Command) !void {
         var params = ParamList.init(self.allocator);
         defer params.deinit();
 
+        var map = ParamMap.init(self.allocator);
+        defer map.deinit();
+
         return switch (cmd.command) {
             .Noop => {},
             .Load => blk: {
@@ -384,6 +399,24 @@ pub const Runner = struct {
                 try self.revDelayCmd(pos, params);
             },
 
+            .Noise => blk: {
+                const pos = try cmd.consumePosition();
+
+                try cmd.appendParamMap(&map, "seed");
+                try cmd.appendParamMap(&map, "fill_bytes");
+
+                try self.noiseCmd(pos, &map);
+            },
+
+            .WildNoise => blk: {
+                const pos = try cmd.consumePosition();
+
+                try cmd.appendParamMap(&map, "seed");
+                try cmd.appendParamMap(&map, "fill_bytes");
+
+                try self.wildNoiseCmd(pos, &map);
+            },
+
             else => blk: {
                 std.debug.warn("Unsupported command: {}\n", cmd.command);
                 break :blk RunError.UnknownCommand;