Files
llama.cpp/tools/llava/mtmd.cpp
Diego Devesa 1d36b3670b llama : move end-user examples to tools directory (#13249)
* llama : move end-user examples to tools directory

---------

Co-authored-by: Xuan Son Nguyen <son@huggingface.co>
2025-05-02 20:27:13 +02:00

709 lines
28 KiB
C++

#include "clip.h"
#include "clip-impl.h"
#include "mtmd.h"
#include "llama.h"
#include <algorithm>
#include <cerrno>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <limits>
#include <vector>
// slice template, used by some llava-uhd models to correctly place the special tokens around image embeddings
// models not having it (llava-1.6) will process embeddings without any special tokens in-between
enum mtmd_slice_tmpl {
MTMD_SLICE_TMPL_NONE,
MTMD_SLICE_TMPL_MINICPMV_2_5,
MTMD_SLICE_TMPL_MINICPMV_2_6,
// TODO @ngxson : add support for idefics (SmolVLM)
};
struct mtmd_context {
struct clip_ctx * ctx_clip;
const struct llama_model * text_model;
std::vector<float> image_embd_v; // image embedding vector
bool print_timings;
int n_threads;
std::string image_marker;
// for minicpmv, we need special tokens in-between slices
mtmd_slice_tmpl slice_tmpl = MTMD_SLICE_TMPL_NONE;
llama_token tok_ov_img_start = LLAMA_TOKEN_NULL; // overview image
llama_token tok_ov_img_end = LLAMA_TOKEN_NULL; // overview image
llama_token tok_slices_start = LLAMA_TOKEN_NULL; // start of all slices
llama_token tok_slices_end = LLAMA_TOKEN_NULL; // end of all slices
llama_token tok_sli_img_start = LLAMA_TOKEN_NULL; // single slice
llama_token tok_sli_img_end = LLAMA_TOKEN_NULL; // single slice
llama_token tok_row_end = LLAMA_TOKEN_NULL; // end of row
bool use_mrope = false; // for Qwen2VL, we need to use M-RoPE
// TODO @ngxson : add timings
mtmd_context(const char * mmproj_fname,
const llama_model * text_model,
const mtmd_context_params & ctx_params) :
text_model (text_model),
print_timings(ctx_params.print_timings),
n_threads (ctx_params.n_threads),
image_marker (ctx_params.image_marker)
{
clip_context_params ctx_clip_params;
ctx_clip_params.use_gpu = ctx_params.use_gpu;
ctx_clip_params.verbosity = ctx_params.verbosity;
ctx_clip = clip_init(mmproj_fname, ctx_clip_params);
if (!ctx_clip) {
throw std::runtime_error(string_format("Failed to load CLIP model from %s\n", mmproj_fname));
}
use_mrope = clip_is_qwen2vl(ctx_clip);
int minicpmv_version = clip_is_minicpmv(ctx_clip);
if (minicpmv_version == 2) {
// minicpmv 2.5 format:
// <image> (overview) </image><slice><image> (slice) </image><image> (slice) </image>\n ... </slice>
slice_tmpl = MTMD_SLICE_TMPL_MINICPMV_2_5;
tok_ov_img_start = lookup_token("<image>");
tok_ov_img_end = lookup_token("</image>");
tok_slices_start = lookup_token("<slice>");
tok_slices_end = lookup_token("</slice>");
tok_sli_img_start = tok_ov_img_start;
tok_sli_img_end = tok_ov_img_end;
tok_row_end = lookup_token("\n");
} else if (minicpmv_version == 3 || minicpmv_version == 4) {
// minicpmv 2.6 format:
// <image> (overview) </image><slice> (slice) </slice><slice> (slice) </slice>\n ...
slice_tmpl = MTMD_SLICE_TMPL_MINICPMV_2_6;
tok_ov_img_start = lookup_token("<image>");
tok_ov_img_end = lookup_token("</image>");
tok_sli_img_start = lookup_token("<slice>");
tok_sli_img_end = lookup_token("</slice>");
tok_row_end = lookup_token("\n");
} else if (minicpmv_version != 0) {
GGML_ASSERT(false && "unsupported minicpmv version");
}
}
~mtmd_context() {
clip_free(ctx_clip);
}
private:
llama_token lookup_token(const std::string & token_text) {
const llama_vocab * vocab = llama_model_get_vocab(text_model);
const int n_vocab = llama_vocab_n_tokens(vocab);
for (int i = 0; i < n_vocab; i++) {
if (token_to_piece(vocab, i, true) == token_text) {
return i;
}
}
return LLAMA_TOKEN_NULL;
}
std::string token_to_piece(const llama_vocab * vocab, llama_token token, bool special) {
std::string piece;
piece.resize(piece.capacity()); // using string internal cache, 15 bytes + '\n'
const int n_chars = llama_token_to_piece(vocab, token, &piece[0], piece.size(), 0, special);
if (n_chars < 0) {
piece.resize(-n_chars);
int check = llama_token_to_piece(vocab, token, &piece[0], piece.size(), 0, special);
GGML_ASSERT(check == -n_chars);
} else {
piece.resize(n_chars);
}
return piece;
}
};
struct mtmd_image_tokens_data {
clip_image_f32_batch batch_f32; // preprocessed image patches
};
struct mtmd_image_tokens {
uint32_t nx; // number of tokens in x direction
uint32_t ny; // number of tokens in y direction
bool use_mrope_pos = false; // use M-RoPE position counting (the whole image is 1 temporal position)
uint32_t n_tokens() const { return nx * ny; }
clip_image_f32_batch batch_f32; // preprocessed image patches
std::string id; // optional user-defined ID, useful for KV cache tracking
};
mtmd_context * mtmd_init_from_file(const char * mmproj_fname,
const struct llama_model * text_model,
const struct mtmd_context_params ctx_params) {
try {
return new mtmd_context(mmproj_fname, text_model, ctx_params);
} catch (const std::exception & e) {
LOG_ERR("%s: error: %s\n", __func__, e.what());
return nullptr;
}
}
void mtmd_free(mtmd_context * ctx) {
if (ctx) {
delete ctx;
}
}
// copied from common_tokenize
static std::vector<llama_token> mtmd_tokenize_text_internal(
const struct llama_vocab * vocab,
const std::string & text,
bool add_special,
bool parse_special) {
// upper limit for the number of tokens
int n_tokens = text.length() + 2 * add_special;
std::vector<llama_token> result(n_tokens);
n_tokens = llama_tokenize(vocab, text.data(), text.length(), result.data(), result.size(), add_special, parse_special);
if (n_tokens < 0) {
result.resize(-n_tokens);
int check = llama_tokenize(vocab, text.data(), text.length(), result.data(), result.size(), add_special, parse_special);
GGML_ASSERT(check == -n_tokens);
} else {
result.resize(n_tokens);
}
return result;
}
int32_t mtmd_tokenize(mtmd_context * ctx,
std::vector<mtmd_input_chunk> & output,
const mtmd_input_text & text,
const std::vector<mtmd_bitmap> & bitmaps) {
auto vocab = llama_model_get_vocab(ctx->text_model);
std::string prompt_modified(text.text);
std::string marker_modified(ctx->image_marker);
projector_type proj_type = clip_get_projector_type(ctx->ctx_clip);
// a bit hacky here, but works for now
// for some models, we need to add prefix and suffix to the image embeddings
if (clip_is_gemma3(ctx->ctx_clip)) {
// gemma 3
// <start_of_image> ... (image embeddings) ... <end_of_image>
marker_modified = "<start_of_image>" + ctx->image_marker + "<end_of_image>";
string_replace_all(prompt_modified, ctx->image_marker, marker_modified);
} else if (proj_type == PROJECTOR_TYPE_GLM_EDGE) {
// <|begin_of_image|> ... (image embeddings) ... <|end_of_image|>
marker_modified = "<|begin_of_image|>" + ctx->image_marker + "<|end_of_image|>";
string_replace_all(prompt_modified, ctx->image_marker, marker_modified);
} else if (proj_type == PROJECTOR_TYPE_IDEFICS3) {
// https://github.com/huggingface/transformers/blob/a42ba80fa520c784c8f11a973ca9034e5f859b79/src/transformers/models/idefics3/processing_idefics3.py#L192-L215
marker_modified = "<fake_token_around_image><global-img>" + ctx->image_marker + "<fake_token_around_image>";
string_replace_all(prompt_modified, ctx->image_marker, marker_modified);
} else if (proj_type == PROJECTOR_TYPE_PIXTRAL) {
// https://github.com/huggingface/transformers/blob/1cd110c6cb6a6237614130c470e9a902dbc1a4bd/docs/source/en/model_doc/pixtral.md
marker_modified = ctx->image_marker + "[IMG_END]";
string_replace_all(prompt_modified, ctx->image_marker, marker_modified);
}
else if (proj_type == PROJECTOR_TYPE_QWEN2VL || proj_type == PROJECTOR_TYPE_QWEN25VL) {
// <|vision_start|> ... (image embeddings) ... <|vision_end|>
marker_modified = "<|vision_start|>" + ctx->image_marker + "<|vision_end|>";
string_replace_all(prompt_modified, ctx->image_marker, marker_modified);
}
// llava-1.5, llava-1.6, Yi-VL, Yi-34B, granite: don't need to add prefix and suffix
std::vector<std::string> parts = string_split_str(prompt_modified, ctx->image_marker);
output.clear();
output.reserve(parts.size());
size_t i_img = 0;
// utility for adding raw tokens
auto add_text_chunk = [&output](std::vector<llama_token> && tokens) {
mtmd_input_chunk chunk{
MTMD_INPUT_CHUNK_TYPE_TEXT,
std::move(tokens),
{},
};
output.emplace_back(std::move(chunk));
};
// utility for splitting batch of multiple images into chunks of batch having single images
auto split_batch_to_chunk = [&ctx](clip_image_f32_batch && batch_f32, const std::string & id) {
std::vector<mtmd_input_chunk> chunks;
for (auto & entry : batch_f32.entries) {
mtmd_image_tokens_ptr image_tokens(new mtmd_image_tokens);
image_tokens->nx = clip_n_output_tokens(ctx->ctx_clip, entry.get());
image_tokens->ny = 1;
image_tokens->batch_f32.entries.push_back(std::move(entry));
image_tokens->id = id;
mtmd_input_chunk chunk{
MTMD_INPUT_CHUNK_TYPE_IMAGE,
{},
std::move(image_tokens),
};
chunks.emplace_back(std::move(chunk));
}
return chunks;
};
for (const auto & part : parts) {
// printf("tokenizing part: %s\n", part.c_str());
bool add_bos = &parts.front() == &part;
auto tokens = mtmd_tokenize_text_internal(vocab, part, text.add_special && add_bos, text.parse_special);
if (tokens.empty()) {
continue;
}
mtmd_input_chunk chunk{
MTMD_INPUT_CHUNK_TYPE_TEXT,
std::move(tokens),
{},
};
output.emplace_back(std::move(chunk));
if (&parts.back() != &part) {
// add image token to middle of 2 parts
if (i_img >= bitmaps.size()) {
LOG_ERR("%s: error: not enough images for %d parts\n", __func__, (int)parts.size());
return 1;
}
// convert mtmd_bitmap to clip_image_u8
clip_image_u8_ptr img_u8(clip_image_u8_init());
img_u8->nx = bitmaps[i_img].nx;
img_u8->ny = bitmaps[i_img].ny;
img_u8->buf.resize(bitmaps[i_img].data.size());
std::memcpy(img_u8->buf.data(), bitmaps[i_img].data.data(), img_u8->nx * img_u8->ny * 3);
clip_image_size img_u8_size{img_u8->nx, img_u8->ny};
// preprocess image
clip_image_f32_batch batch_f32;
bool ok = clip_image_preprocess(ctx->ctx_clip, img_u8.get(), &batch_f32);
if (!ok) {
LOG_ERR("Unable to preprocess image\n");
return 2;
}
if (ctx->slice_tmpl == MTMD_SLICE_TMPL_MINICPMV_2_5 || ctx->slice_tmpl == MTMD_SLICE_TMPL_MINICPMV_2_6) {
// split batch into chunks of single images
auto chunks = split_batch_to_chunk(std::move(batch_f32), bitmaps[i_img].id);
GGML_ASSERT(chunks.size() > 0);
// add overview image
add_text_chunk({ctx->tok_ov_img_start});
output.emplace_back(std::move(chunks.front()));
chunks.erase(chunks.begin());
add_text_chunk({ctx->tok_ov_img_end});
// add slices
if (!chunks.empty()) {
clip_add_load_image_size(ctx->ctx_clip, &img_u8_size);
int n_col = clip_uhd_num_image_embeds_col(ctx->ctx_clip);
int n_row = (int)chunks.size() / n_col;
GGML_ASSERT(n_row * n_col == (int)chunks.size());
if (ctx->tok_slices_start != LLAMA_TOKEN_NULL) {
add_text_chunk({ctx->tok_slices_start});
}
for (int y = 0; y < n_row; y++) {
for (int x = 0; x < n_col; x++) {
if (ctx->tok_sli_img_start != LLAMA_TOKEN_NULL) {
add_text_chunk({ctx->tok_sli_img_start});
}
output.emplace_back(std::move(chunks[y * n_col + x]));
if (ctx->tok_sli_img_end != LLAMA_TOKEN_NULL) {
add_text_chunk({ctx->tok_sli_img_end});
}
}
if (ctx->tok_row_end != LLAMA_TOKEN_NULL && y != n_row - 1) {
add_text_chunk({ctx->tok_row_end});
}
}
if (ctx->tok_slices_end != LLAMA_TOKEN_NULL) {
add_text_chunk({ctx->tok_slices_end});
}
}
} else {
size_t n_tokens = 0;
for (const auto & entry : batch_f32.entries) {
n_tokens += clip_n_output_tokens(ctx->ctx_clip, entry.get());
}
mtmd_image_tokens_ptr image_tokens(new mtmd_image_tokens);
if (ctx->use_mrope) {
// for Qwen2VL, we need this information for M-RoPE decoding positions
image_tokens->nx = clip_n_output_tokens_x(ctx->ctx_clip, batch_f32.entries[0].get());
image_tokens->ny = clip_n_output_tokens_y(ctx->ctx_clip, batch_f32.entries[0].get());
image_tokens->use_mrope_pos = true;
} else {
// other models, we only need the total number of tokens
image_tokens->nx = n_tokens;
image_tokens->ny = 1;
}
image_tokens->batch_f32 = std::move(batch_f32);
image_tokens->id = bitmaps[i_img].id; // optional
LOG_DBG("image_tokens->nx = %d\n", image_tokens->nx);
LOG_DBG("image_tokens->ny = %d\n", image_tokens->ny);
LOG_DBG("batch_f32 size = %d\n", (int)image_tokens->batch_f32.entries.size());
mtmd_input_chunk chunk{
MTMD_INPUT_CHUNK_TYPE_IMAGE,
{},
std::move(image_tokens),
};
output.emplace_back(std::move(chunk));
}
i_img++; // move to next image
}
}
return 0;
}
void mtmd_image_tokens_free(mtmd_image_tokens * image_tokens) {
if (image_tokens) {
delete image_tokens;
}
}
size_t mtmd_image_tokens_get_n_tokens(const mtmd_image_tokens * image_tokens) {
return image_tokens->n_tokens();
}
size_t mtmd_image_tokens_get_nx(const mtmd_image_tokens * image_tokens) {
return image_tokens->nx;
}
size_t mtmd_image_tokens_get_ny(const mtmd_image_tokens * image_tokens) {
return image_tokens->ny;
}
std::string mtmd_image_tokens_get_id(const mtmd_image_tokens * image_tokens) {
return image_tokens->id;
}
llama_pos mtmd_image_tokens_get_n_pos(const mtmd_image_tokens * image_tokens) {
if (image_tokens->use_mrope_pos) {
return 1; // for M-RoPE, the whole image is 1 in temporal dimension
}
return image_tokens->n_tokens();
}
int32_t mtmd_encode(mtmd_context * ctx, const mtmd_image_tokens * image_tokens) {
int n_mmproj_embd = clip_n_mmproj_embd(ctx->ctx_clip);
ctx->image_embd_v.resize(image_tokens->n_tokens() * n_mmproj_embd);
bool ok = false;
// only effective for minicpmv and qwen2vl, other models will ignore load_image_size
{
clip_image_size slice_size{
image_tokens->batch_f32.entries[0]->nx,
image_tokens->batch_f32.entries[0]->ny};
clip_add_load_image_size(ctx->ctx_clip, &slice_size);
}
if (clip_is_llava(ctx->ctx_clip) || clip_is_minicpmv(ctx->ctx_clip) || clip_is_glm(ctx->ctx_clip)) {
// TODO @ngxson : llava does not support batched encoding ; this should be fixed inside clip_image_batch_encode()
const auto & entries = image_tokens->batch_f32.entries;
for (size_t i = 0; i < entries.size(); i++) {
int n_tokens_per_image = clip_n_output_tokens(ctx->ctx_clip, entries[i].get());
ok = clip_image_encode(
ctx->ctx_clip,
ctx->n_threads,
entries[i].get(),
ctx->image_embd_v.data() + i*n_mmproj_embd*n_tokens_per_image);
}
} else {
ok = clip_image_batch_encode(
ctx->ctx_clip,
ctx->n_threads,
&image_tokens->batch_f32,
ctx->image_embd_v.data());
}
return ok ? 0 : 1;
}
float * mtmd_get_output_embd(mtmd_context * ctx) {
return ctx->image_embd_v.data();
}
size_t mtmd_helper_get_n_tokens(mtmd_input_chunks & chunks) {
size_t n_tokens = 0;
for (auto & chunk : chunks) {
if (chunk.type == MTMD_INPUT_CHUNK_TYPE_TEXT) {
n_tokens += chunk.tokens_text.size();
} else if (chunk.type == MTMD_INPUT_CHUNK_TYPE_IMAGE) {
n_tokens += mtmd_image_tokens_get_n_tokens(chunk.tokens_image.get());
} else {
GGML_ASSERT(false && "chunk type not supported");
}
}
return n_tokens;
}
llama_pos mtmd_helper_get_n_pos(mtmd_input_chunks & chunks) {
llama_pos n_pos = 0;
for (auto & chunk : chunks) {
if (chunk.type == MTMD_INPUT_CHUNK_TYPE_TEXT) {
n_pos += chunk.tokens_text.size();
} else if (chunk.type == MTMD_INPUT_CHUNK_TYPE_IMAGE) {
n_pos += mtmd_image_tokens_get_n_pos(chunk.tokens_image.get());
} else {
GGML_ASSERT(false && "chunk type not supported");
}
}
return n_pos;
}
// helper struct to make working with embd batch easier
// note: this will be removed after llama_batch_ext refactoring
struct decode_embd_batch {
int n_pos_per_embd;
int n_mmproj_embd;
std::vector<llama_pos> pos;
std::vector<llama_pos> pos_view; // used by mrope
std::vector<int32_t> n_seq_id;
std::vector<llama_seq_id> seq_id_0;
std::vector<llama_seq_id *> seq_ids;
std::vector<int8_t> logits;
llama_batch batch;
decode_embd_batch(float * embd, int32_t n_tokens, int n_pos_per_embd, int n_mmproj_embd) : n_pos_per_embd(n_pos_per_embd), n_mmproj_embd(n_mmproj_embd) {
pos .resize(n_tokens * n_pos_per_embd);
n_seq_id.resize(n_tokens);
seq_ids .resize(n_tokens + 1);
logits .resize(n_tokens);
seq_id_0.resize(1);
seq_ids [n_tokens] = nullptr;
batch = {
/*n_tokens =*/ n_tokens,
/*tokens =*/ nullptr,
/*embd =*/ embd,
/*pos =*/ pos.data(),
/*n_seq_id =*/ n_seq_id.data(),
/*seq_id =*/ seq_ids.data(),
/*logits =*/ logits.data(),
};
}
void set_position_normal(llama_pos pos_0, llama_seq_id seq_id) {
seq_id_0[0] = seq_id;
for (int i = 0; i < batch.n_tokens; i++) {
batch.pos [i] = pos_0 + i;
batch.n_seq_id[i] = 1;
batch.seq_id [i] = seq_id_0.data();
batch.logits [i] = false;
}
}
void set_position_mrope(llama_pos pos_0, int nx, int ny, llama_seq_id seq_id) {
GGML_ASSERT(n_pos_per_embd == 4);
seq_id_0[0] = seq_id;
for (int y = 0; y < ny; y++) {
for (int x = 0; x < nx; x++) {
int i = y * nx + x;
pos[i ] = pos_0;
pos[i + batch.n_tokens ] = pos_0 + y;
pos[i + batch.n_tokens * 2] = pos_0 + x;
pos[i + batch.n_tokens * 3] = 0; // last pos dim is unused
}
}
for (int i = 0; i < batch.n_tokens; i++) {
batch.n_seq_id[i] = 1;
batch.seq_id [i] = seq_id_0.data();
batch.logits [i] = false;
}
}
llama_batch get_view(int offset, int n_tokens) {
llama_pos * pos_ptr;
pos_view.clear();
pos_view.resize(n_tokens * n_pos_per_embd);
if (n_pos_per_embd > 1) {
// mrope
// for example, with layout of src: 1234...1234...1234...1234...
// offset 2 will give us dst: 34...34...34...34...
for (int i = 0; i < n_pos_per_embd; i++) {
auto src = pos.begin() + i * batch.n_tokens + offset;
pos_view.insert(pos_view.end(), src, src + n_tokens);
}
pos_ptr = pos_view.data();
} else {
// normal
pos_ptr = pos.data() + offset;
}
return {
/*n_tokens =*/ n_tokens,
/*tokens =*/ nullptr,
/*embd =*/ batch.embd + offset * n_mmproj_embd,
/*pos =*/ pos_ptr,
/*n_seq_id =*/ batch.n_seq_id + offset,
/*seq_id =*/ batch.seq_id + offset,
/*logits =*/ batch.logits + offset,
};
}
};
int32_t mtmd_helper_eval(mtmd_context * ctx,
llama_context * lctx,
mtmd_input_chunks & chunks,
llama_pos pos0,
llama_seq_id seq_id,
int32_t n_batch) {
int32_t ret;
llama_pos n_past = pos0;
llama_batch text_batch = llama_batch_init(n_batch, 0, 1);
int n_mmproj_embd = clip_n_mmproj_embd(ctx->ctx_clip);
int n_pos_per_embd = mtmd_decode_use_mrope(ctx) ? 4 : 1;
for (auto & chunk : chunks) {
bool is_last = &chunk == &chunks.back();
if (chunk.type == MTMD_INPUT_CHUNK_TYPE_TEXT) {
text_batch.n_tokens = chunk.tokens_text.size();
size_t i = 0;
while (i < chunk.tokens_text.size()) { // split into batches
for (; i < chunk.tokens_text.size() && text_batch.n_tokens < n_batch; i++) {
text_batch.token [i] = chunk.tokens_text[i];
text_batch.pos [i] = n_past++;
text_batch.n_seq_id[i] = 1;
text_batch.seq_id [i][0] = seq_id;
text_batch.logits [i] = false;
}
if (is_last) {
// always get logits for last input chunk
text_batch.logits[text_batch.n_tokens - 1] = true;
}
ret = llama_decode(lctx, text_batch);
if (ret != 0) {
LOG_ERR("failed to decode text\n");
llama_batch_free(text_batch);
return ret;
}
}
} else if (chunk.type == MTMD_INPUT_CHUNK_TYPE_IMAGE) {
GGML_ASSERT(!is_last && "logits for last image chunk is not yet supported");
GGML_ASSERT(chunk.tokens_image != nullptr);
int64_t t0 = ggml_time_ms();
if (ctx->print_timings) {
LOG_INF("encoding image or slice...\n");
}
ret = mtmd_encode(ctx, chunk.tokens_image.get());
if (ret != 0) {
LOG_ERR("failed to encode image\n");
llama_batch_free(text_batch);
return ret;
}
if (ctx->print_timings) {
LOG_INF("image/slice encoded in %" PRId64 " ms\n", ggml_time_ms() - t0);
}
int32_t n_tokens = mtmd_image_tokens_get_n_tokens(chunk.tokens_image.get());
int32_t i_batch = 0;
int32_t n_img_batches = GGML_PAD(n_tokens, n_batch) / n_batch;
float * embd = mtmd_get_output_embd(ctx);
decode_embd_batch batch_embd(embd, n_tokens, n_pos_per_embd, n_mmproj_embd);
const int nx = mtmd_image_tokens_get_nx(chunk.tokens_image.get());
const int ny = mtmd_image_tokens_get_ny(chunk.tokens_image.get());
if (mtmd_decode_use_mrope(ctx)) {
batch_embd.set_position_mrope(n_past, nx, ny, seq_id);
} else {
batch_embd.set_position_normal(n_past, seq_id);
}
if (mtmd_decode_use_non_causal(ctx)) {
llama_set_causal_attn(lctx, false);
// TODO @ngxson : need to make sure only one image is processed at a time, and n_ubatch must be enough to hold the image
}
while (i_batch < n_img_batches) { // split into batches
int pos_offset = i_batch*n_batch;
int n_tokens_batch = std::min(n_batch, n_tokens - pos_offset);
llama_batch batch_embd_view = batch_embd.get_view(pos_offset, n_tokens_batch);
LOG_INF("decoding image batch %d/%d, n_tokens_batch = %d\n", i_batch+1, n_img_batches, n_tokens_batch);
int64_t t1 = ggml_time_ms();
ret = llama_decode(lctx, batch_embd_view);
if (ret != 0) {
LOG_ERR("failed to decode image\n");
llama_set_causal_attn(lctx, true); // restore causal attn
llama_batch_free(text_batch);
return ret;
}
if (ctx->print_timings) {
LOG_INF("image decoded (batch %d/%d) in %" PRId64 " ms\n", i_batch+1, n_img_batches, ggml_time_ms() - t1);
}
i_batch++;
}
// for mrope, one image is one single **temporal** position
n_past += mtmd_decode_use_mrope(ctx) ? 1 : n_tokens;
if (mtmd_decode_use_non_causal(ctx)) {
llama_set_causal_attn(lctx, true);
}
} else {
GGML_ASSERT(false && "chunk type not supported");
}
}
llama_batch_free(text_batch);
return 0;
}
int32_t mtmd_helper_bitmap_init_from_buf(const unsigned char * buf, size_t len, mtmd_bitmap & output) {
clip_image_u8_ptr img_u8(clip_image_u8_init());
bool ok = clip_image_load_from_bytes(buf, len, img_u8.get());
if (!ok) {
LOG_ERR("Unable to load image from buffer\n");
return 1;
}
unsigned char * data = clip_image_u8_get_data(img_u8.get(), &output.nx, &output.ny);
output.data.resize(output.nx * output.ny * 3);
std::memcpy(output.data.data(), data, output.nx * output.ny * 3);
return 0;
}
int32_t mtmd_helper_bitmap_init_from_file(const char * fname, mtmd_bitmap & output) {
clip_image_u8_ptr img_u8(clip_image_u8_init());
bool ok = clip_image_load_from_file(fname, img_u8.get());
if (!ok) {
LOG_ERR("Unable to load image %s\n", fname);
return 1;
}
unsigned char * data = clip_image_u8_get_data(img_u8.get(), &output.nx, &output.ny);
output.data.resize(output.nx * output.ny * 3);
std::memcpy(output.data.data(), data, output.nx * output.ny * 3);
return 0;
}
bool mtmd_decode_use_non_causal(mtmd_context * ctx) {
projector_type proj_type = clip_get_projector_type(ctx->ctx_clip);
if (proj_type == PROJECTOR_TYPE_GEMMA3) {
return true;
}
return false;
}
bool mtmd_decode_use_mrope(mtmd_context * ctx) {
return ctx->use_mrope;
}
void mtmd_image_tokens_deleter::operator()(mtmd_image_tokens * val) {
mtmd_image_tokens_free(val);
}