add base64 in-prompt image support

examples/llava/base64.hpp

@@ -0,0 +1,392 @@
+/*
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+For more information, please refer to <http://unlicense.org>
+*/
+
+#ifndef PUBLIC_DOMAIN_BASE64_HPP_
+#define PUBLIC_DOMAIN_BASE64_HPP_
+
+#include <cstdint>
+#include <iterator>
+#include <stdexcept>
+#include <string>
+
+class base64_error : public std::runtime_error
+{
+public:
+	using std::runtime_error::runtime_error;
+};
+
+class base64
+{
+public:
+	enum class alphabet
+	{
+		/** the alphabet is detected automatically */
+		auto_,
+		/** the standard base64 alphabet is used */
+		standard,
+		/** like `standard` except that the characters `+` and `/` are replaced by `-` and `_` respectively*/
+		url_filename_safe
+	};
+
+	enum class decoding_behavior
+	{
+		/** if the input is not padded, the remaining bits are ignored */
+		moderate,
+		/** if a padding character is encounter decoding is finished */
+		loose
+	};
+
+	/**
+	 Encodes all the elements from `in_begin` to `in_end` to `out`.
+
+	 @warning The source and destination cannot overlap. The destination must be able to hold at least
+	 `required_encode_size(std::distance(in_begin, in_end))`, otherwise the behavior depends on the output iterator.
+
+	 @tparam Input_iterator the source; the returned elements are cast to `std::uint8_t` and should not be greater than
+	 8 bits
+	 @tparam Output_iterator the destination; the elements written to it are from the type `char`
+	 @param in_begin the beginning of the source
+	 @param in_end the ending of the source
+	 @param out the destination iterator
+	 @param alphabet which alphabet should be used
+	 @returns the iterator to the next element past the last element copied
+	 @throws see `Input_iterator` and `Output_iterator`
+	*/
+	template<typename Input_iterator, typename Output_iterator>
+	static Output_iterator encode(Input_iterator in_begin, Input_iterator in_end, Output_iterator out,
+	                              alphabet alphabet = alphabet::standard)
+	{
+		constexpr auto pad = '=';
+		const char* alpha  = alphabet == alphabet::url_filename_safe
+		                        ? "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"
+		                        : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+		while (in_begin != in_end) {
+			std::uint8_t i0 = 0, i1 = 0, i2 = 0;
+
+			// first character
+			i0 = static_cast<std::uint8_t>(*in_begin);
+			++in_begin;
+
+			*out = alpha[i0 >> 2 & 0x3f];
+			++out;
+
+			// part of first character and second
+			if (in_begin != in_end) {
+				i1 = static_cast<std::uint8_t>(*in_begin);
+				++in_begin;
+
+				*out = alpha[((i0 & 0x3) << 4) | (i1 >> 4 & 0x0f)];
+				++out;
+			} else {
+				*out = alpha[(i0 & 0x3) << 4];
+				++out;
+
+				// last padding
+				*out = pad;
+				++out;
+
+				// last padding
+				*out = pad;
+				++out;
+
+				break;
+			}
+
+			// part of second character and third
+			if (in_begin != in_end) {
+				i2 = static_cast<std::uint8_t>(*in_begin);
+				++in_begin;
+
+				*out = alpha[((i1 & 0xf) << 2) | (i2 >> 6 & 0x03)];
+				++out;
+			} else {
+				*out = alpha[(i1 & 0xf) << 2];
+				++out;
+
+				// last padding
+				*out = pad;
+				++out;
+
+				break;
+			}
+
+			// rest of third
+			*out = alpha[i2 & 0x3f];
+			++out;
+		}
+
+		return out;
+	}
+	/**
+	 Encodes a string.
+
+	 @param str the string that should be encoded
+	 @param alphabet which alphabet should be used
+	 @returns the encoded base64 string
+	 @throws see base64::encode()
+	*/
+	static std::string encode(const std::string& str, alphabet alphabet = alphabet::standard)
+	{
+		std::string result;
+
+		result.reserve(required_encode_size(str.length()) + 1);
+
+		encode(str.begin(), str.end(), std::back_inserter(result), alphabet);
+
+		return result;
+	}
+	/**
+	 Encodes a char array.
+
+	 @param buffer the char array
+	 @param size the size of the array
+	 @param alphabet which alphabet should be used
+	 @returns the encoded string
+	*/
+	static std::string encode(const char* buffer, std::size_t size, alphabet alphabet = alphabet::standard)
+	{
+		std::string result;
+
+		result.reserve(required_encode_size(size) + 1);
+
+		encode(buffer, buffer + size, std::back_inserter(result), alphabet);
+
+		return result;
+	}
+	/**
+	 Decodes all the elements from `in_begin` to `in_end` to `out`. `in_begin` may point to the same location as `out`,
+	 in other words: inplace decoding is possible.
+
+	 @warning The destination must be able to hold at least `required_decode_size(std::distance(in_begin, in_end))`,
+	 otherwise the behavior depends on the output iterator.
+
+	 @tparam Input_iterator the source; the returned elements are cast to `char`
+	 @tparam Output_iterator the destination; the elements written to it are from the type `std::uint8_t`
+	 @param in_begin the beginning of the source
+	 @param in_end the ending of the source
+	 @param out the destination iterator
+	 @param alphabet which alphabet should be used
+	 @param behavior the behavior when an error was detected
+	 @returns the iterator to the next element past the last element copied
+	 @throws base64_error depending on the set behavior
+	 @throws see `Input_iterator` and `Output_iterator`
+	*/
+	template<typename Input_iterator, typename Output_iterator>
+	static Output_iterator decode(Input_iterator in_begin, Input_iterator in_end, Output_iterator out,
+	                              alphabet alphabet          = alphabet::auto_,
+	                              decoding_behavior behavior = decoding_behavior::moderate)
+	{
+		//constexpr auto pad = '=';
+		std::uint8_t last  = 0;
+		auto bits          = 0;
+
+		while (in_begin != in_end) {
+			auto c = *in_begin;
+			++in_begin;
+
+			if (c == '=') {
+				break;
+			}
+
+			auto part = _base64_value(alphabet, c);
+
+			// enough bits for one byte
+			if (bits + 6 >= 8) {
+				*out = (last << (8 - bits)) | (part >> (bits - 2));
+				++out;
+
+				bits -= 2;
+			} else {
+				bits += 6;
+			}
+
+			last = part;
+		}
+
+		// check padding
+		if (behavior != decoding_behavior::loose) {
+			while (in_begin != in_end) {
+				auto c = *in_begin;
+				++in_begin;
+
+				if (c != '=') {
+					throw base64_error("invalid base64 character.");
+				}
+			}
+		}
+
+		return out;
+	}
+	/**
+	 Decodes a string.
+
+	 @param str the base64 encoded string
+	 @param alphabet which alphabet should be used
+	 @param behavior the behavior when an error was detected
+	 @returns the decoded string
+	 @throws see base64::decode()
+	*/
+	static std::string decode(const std::string& str, alphabet alphabet = alphabet::auto_,
+	                          decoding_behavior behavior = decoding_behavior::moderate)
+	{
+		std::string result;
+
+		result.reserve(max_decode_size(str.length()));
+
+		decode(str.begin(), str.end(), std::back_inserter(result), alphabet, behavior);
+
+		return result;
+	}
+	/**
+	 Decodes a string.
+
+	 @param buffer the base64 encoded buffer
+	 @param size the size of the buffer
+	 @param alphabet which alphabet should be used
+	 @param behavior the behavior when an error was detected
+	 @returns the decoded string
+	 @throws see base64::decode()
+	*/
+	static std::string decode(const char* buffer, std::size_t size, alphabet alphabet = alphabet::auto_,
+	                          decoding_behavior behavior = decoding_behavior::moderate)
+	{
+		std::string result;
+
+		result.reserve(max_decode_size(size));
+
+		decode(buffer, buffer + size, std::back_inserter(result), alphabet, behavior);
+
+		return result;
+	}
+	/**
+	 Decodes a string inplace.
+
+	 @param[in,out] str the base64 encoded string
+	 @param alphabet which alphabet should be used
+	 @param behavior the behavior when an error was detected
+	 @throws base64::decode_inplace()
+	*/
+	static void decode_inplace(std::string& str, alphabet alphabet = alphabet::auto_,
+	                           decoding_behavior behavior = decoding_behavior::moderate)
+	{
+		str.resize(decode(str.begin(), str.end(), str.begin(), alphabet, behavior) - str.begin());
+	}
+	/**
+	 Decodes a char array inplace.
+
+	 @param[in,out] str the string array
+	 @param size the length of the array
+	 @param alphabet which alphabet should be used
+	 @param behavior the behavior when an error was detected
+	 @returns the pointer to the next element past the last element decoded
+	 @throws base64::decode_inplace()
+	*/
+	static char* decode_inplace(char* str, std::size_t size, alphabet alphabet = alphabet::auto_,
+	                            decoding_behavior behavior = decoding_behavior::moderate)
+	{
+		return decode(str, str + size, str, alphabet, behavior);
+	}
+	/**
+	 Returns the required decoding size for a given size. The value is calculated with the following formula:
+
+	 $$
+	 \lceil \frac{size}{4} \rceil \cdot 3
+	 $$
+
+	 @param size the size of the encoded input
+	 @returns the size of the resulting decoded buffer; this the absolute maximum
+	*/
+	static std::size_t max_decode_size(std::size_t size) noexcept
+	{
+		return (size / 4 + (size % 4 ? 1 : 0)) * 3;
+	}
+	/**
+	 Returns the required encoding size for a given size. The value is calculated with the following formula:
+
+	 $$
+	 \lceil \frac{size}{3} \rceil \cdot 4
+	 $$
+
+	 @param size the size of the decoded input
+	 @returns the size of the resulting encoded buffer
+	*/
+	static std::size_t required_encode_size(std::size_t size) noexcept
+	{
+		return (size / 3 + (size % 3 ? 1 : 0)) * 4;
+	}
+
+private:
+	static std::uint8_t _base64_value(alphabet& alphabet, char c)
+	{
+		if (c >= 'A' && c <= 'Z') {
+			return c - 'A';
+		} else if (c >= 'a' && c <= 'z') {
+			return c - 'a' + 26;
+		} else if (c >= '0' && c <= '9') {
+			return c - '0' + 52;
+		}
+
+		// comes down to alphabet
+		if (alphabet == alphabet::standard) {
+			if (c == '+') {
+				return 62;
+			} else if (c == '/') {
+				return 63;
+			}
+		} else if (alphabet == alphabet::url_filename_safe) {
+			if (c == '-') {
+				return 62;
+			} else if (c == '_') {
+				return 63;
+			}
+		} // auto detect
+		else {
+			if (c == '+') {
+				alphabet = alphabet::standard;
+
+				return 62;
+			} else if (c == '/') {
+				alphabet = alphabet::standard;
+
+				return 63;
+			} else if (c == '-') {
+				alphabet = alphabet::url_filename_safe;
+
+				return 62;
+			} else if (c == '_') {
+				alphabet = alphabet::url_filename_safe;
+
+				return 63;
+			}
+		}
+
+		throw base64_error("invalid base64 character.");
+	}
+};
+
+#endif // !PUBLIC_DOMAIN_BASE64_HPP_

examples/llava/llava.cpp

@@ -8,6 +8,8 @@
 #include <cstdlib>
 #include <vector>
 
+#include "base64.hpp"
+
 static void show_additional_info(int /*argc*/, char ** argv) {
     printf("\n example usage: %s -m <llava-v1.5-7b/ggml-model-q5_k.gguf> --mmproj <llava-v1.5-7b/mmproj-model-f16.gguf> --image <path/to/an/image.jpg> [--temp 0.1] [-p \"describe the image in detail.\"]\n", argv[0]);
     printf("  note: a lower temperature value like 0.1 is recommended for better quality.\n");
@@ -35,13 +37,67 @@ static bool encode_image_with_clip(clip_ctx * ctx_clip, int n_threads, const cli
     return true;
 }
 
+static const char* IMG_BASE64_TAG_BEGIN = "<img src=\"data:image/jpeg;base64,";
+static const char* IMG_BASE64_TAG_END = "\">";
+
+static void find_image_tag_in_prompt(const std::string& prompt, size_t& begin_out, size_t& end_out) {
+    begin_out = prompt.find(IMG_BASE64_TAG_BEGIN);
+    end_out = prompt.find(IMG_BASE64_TAG_END, (begin_out == std::string::npos) ? 0UL : begin_out);
+}
+
+static bool prompt_contains_image(const std::string& prompt) {
+    size_t begin, end;
+    find_image_tag_in_prompt(prompt, begin, end);
+    return (begin != std::string::npos);
+}
+
+// replaces the base64 image tag in the prompt with `replacement`
+static bool get_image_from_prompt(const std::string& prompt, clip_image_u8 * img) {    
+    size_t img_base64_str_start, img_base64_str_end;
+    find_image_tag_in_prompt(prompt, img_base64_str_start, img_base64_str_end);
+    if (img_base64_str_start == std::string::npos || img_base64_str_end == std::string::npos) {
+        fprintf(stderr, "%s: invalid base64 image tag. must be %s<base64 byte string>%s\n", __func__, IMG_BASE64_TAG_BEGIN, IMG_BASE64_TAG_END);
+        return false;
+    }
+
+    auto base64_bytes_start = img_base64_str_start + strlen(IMG_BASE64_TAG_BEGIN);
+    auto base64_bytes_count = img_base64_str_end - base64_bytes_start;
+    auto base64_str = prompt.substr(base64_bytes_start, base64_bytes_count );
+    printf("base64_str: '%s'\n", base64_str.c_str());
+
+    auto required_bytes = base64::required_encode_size(base64_str.size());
+    auto img_bytes = std::vector<unsigned char>(required_bytes);
+    auto img_bytes_end = base64::decode(base64_str.begin(), base64_str.end(), img_bytes.begin());
+    auto img_bytes_len = img_bytes_end - img_bytes.begin();
+
+    auto img_loaded_ok = clip_image_load_from_bytes(img_bytes.data(), img_bytes_len, img);
+    if (!img_loaded_ok) {
+        fprintf(stderr, "%s: could not load image from base64 string.\n", __func__);
+        return false;
+    }
+
+    return true;
+}
+
+static std::string remove_image_from_prompt(const std::string& prompt, const char * replacement = "") {
+    size_t begin, end;
+    find_image_tag_in_prompt(prompt, begin, end);
+    if (begin == std::string::npos || end == std::string::npos) {
+        return prompt;
+    }
+    auto pre = prompt.substr(0, begin);
+    auto post = prompt.substr(end+1);
+    return pre + replacement + post;
+}
+
 struct llava_context * llava_init(gpt_params * params) {
 
     const char * clip_path = params->mmproj.c_str();
     const char * img_path = params->image.c_str();
 
-    if (params->prompt.empty()) {
-        params->prompt = "describe the image in detail.";
+    auto prompt = params->prompt;
+    if (prompt.empty()) {
+        prompt = "describe the image in detail.";
     }
     
     auto ctx_clip = clip_model_load(clip_path, /*verbosity=*/ 1);
@@ -49,10 +105,22 @@ struct llava_context * llava_init(gpt_params * params) {
     // load and preprocess the image
     clip_image_u8 img;
 
-    if (!clip_image_load_from_file(img_path, &img)) {
-        fprintf(stderr, "%s: is %s really an image file?\n", __func__, img_path);
-        clip_free(ctx_clip);
-        return NULL;
+    if (prompt_contains_image(prompt)) {
+        if (img_path) {
+            printf("using base64 encoded image instead of command line image path\n");
+        }
+        if (!get_image_from_prompt(prompt, &img)) {
+            fprintf(stderr, "%s: can't load image from prompt\n", __func__);
+            clip_free(ctx_clip);
+            return NULL;
+        }
+        prompt = remove_image_from_prompt(prompt);
+    } else {
+        if (!clip_image_load_from_file(img_path, &img)) {
+            fprintf(stderr, "%s: is %s really an image file?\n", __func__, img_path);
+            clip_free(ctx_clip);
+            return NULL;
+        }
     }
 
     float * image_embd = (float *)malloc(clip_embd_nbytes(ctx_clip));
@@ -169,7 +237,7 @@ int main(int argc, char ** argv) {
         show_additional_info(argc, argv);
         return 1;
     }
-    if (params.mmproj.empty() || params.image.empty()) {
+    if (params.mmproj.empty() || (params.image.empty() && !prompt_contains_image(params.prompt))) {
         gpt_print_usage(argc, argv, params);
         show_additional_info(argc, argv);
         return 1;