文档理解

Gemini 模型可以处理 PDF 格式的文档,并使用原生视觉功能来理解整个文档的上下文。这不仅仅是提取文本,还让 Gemini 能够:

  • 分析和解读内容,包括文本、图像、图表、图表和表格,即使是长达 1,000 页的文档也能轻松应对。
  • 将信息提取为结构化输出格式。
  • 根据文档中的视觉和文本元素总结内容并回答问题。
  • 转写文档内容(例如转写为 HTML),同时保留布局和格式,以便在下游应用中使用。

您也可以通过相同的方式传递非 PDF 文档,但 Gemini 会将这些文档视为普通文本,从而消除图表或格式等上下文。

以内嵌方式传递 PDF 数据

您可以在请求中内嵌传递 PDF 数据。此方法最适合处理较小的文档或临时处理,因为您无需在后续请求中引用该文件。对于需要在多轮对话中参考的较大文档,我们建议使用 Files API,以缩短请求延迟时间并减少带宽使用量。

以下示例展示了如何以内嵌方式传递 PDF 数据:

Python

from google import genai
import base64

client = genai.Client()

with open('path/to/document.pdf', 'rb') as f:
    pdf_bytes = f.read()

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {
            "type": "document",
            "data": base64.b64encode(pdf_bytes).decode('utf-8'),
            "mime_type": "application/pdf"
        },
        {"type": "text", "text": "Summarize this document"}
    ]
)

print(interaction.steps[-1].content[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";
import * as fs from "node:fs";

const ai = new GoogleGenAI({});

async function main() {
    const pdfData = fs.readFileSync("path/to/document.pdf", {
        encoding: "base64"
    });

    const interaction = await ai.interactions.create({
        model: "gemini-3-flash-preview",
        input: [
            { type: "text", text: "Summarize this document" },
            {
                type: "document",
                data: pdfData,
                mimeType: "application/pdf"
            }
        ]
    });
    console.log(interaction.steps.at(-1).content[0].text);
}

main();

REST

PDF_PATH="path/to/document.pdf"

if [[ "$(base64 --version 2>&1)" = *"FreeBSD"* ]]; then
  B64FLAGS="--input"
else
  B64FLAGS="-w0"
fi

curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "gemini-3-flash-preview",
    "input": [
      {
        "type": "document",
        "data": "'$(base64 $B64FLAGS $PDF_PATH)'",
        "mimeType": "application/pdf"
      },
      {"type": "text", "text": "Summarize this document"}
    ]
  }'

您还可以上传本地 PDF 文件以进行处理:

Python

from google import genai

client = genai.Client()

uploaded_file = client.files.upload(file="file.pdf")

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {"type": "document", "uri": uploaded_file.uri, "mime_type": uploaded_file.mime_type},
        {"type": "text", "text": "Summarize this document"}
    ]
)
print(interaction.steps[-1].content[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
    const uploadedFile = await ai.files.upload({
        file: "file.pdf",
        config: { mimeType: "application/pdf" }
    });

    const interaction = await ai.interactions.create({
        model: "gemini-3-flash-preview",
        input: [
            { type: "text", text: "Summarize this document" },
            {
                type: "document",
                uri: uploadedFile.uri,
                mimeType: uploadedFile.mimeType
            }
        ]
    });
    console.log(interaction.steps.at(-1).content[0].text);
}

main();

使用 Files API 上传 PDF

建议您使用 Files API 处理较大的文件,或者打算在多个请求中重复使用某个文档时使用该 API。通过将文件上传与模型请求分离,可以缩短请求延迟时间并减少带宽使用量。

来自网址的大型 PDF 文件

使用 File API 可简化通过网址上传和处理大型 PDF 文件的流程:

Python

from google import genai
import io
import httpx

client = genai.Client()

long_context_pdf_path = "https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf"

# Retrieve and upload the PDF using the File API
doc_io = io.BytesIO(httpx.get(long_context_pdf_path).content)

sample_doc = client.files.upload(
  # You can pass a path or a file-like object here
  file=doc_io,
  config=dict(
    mime_type='application/pdf')
)

prompt = "Summarize this document"

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {"type": "document", "uri": sample_doc.uri, "mime_type": sample_doc.mime_type},
        {"type": "text", "text": prompt}
    ]
)
print(interaction.steps[-1].content[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {

    const pdfBuffer = await fetch("https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf")
        .then((response) => response.arrayBuffer());

    const fileBlob = new Blob([pdfBuffer], { type: 'application/pdf' });

    const file = await ai.files.upload({
        file: fileBlob,
        config: {
            displayName: 'A17_FlightPlan.pdf',
        },
    });

    // Wait for the file to be processed.
    let getFile = await ai.files.get({ name: file.name });
    while (getFile.state === 'PROCESSING') {
        getFile = await ai.files.get({ name: file.name });
        console.log(`current file status: ${getFile.state}`);
        console.log('File is still processing, retrying in 5 seconds');

        await new Promise((resolve) => {
            setTimeout(resolve, 5000);
        });
    }
    if (file.state === 'FAILED') {
        throw new Error('File processing failed.');
    }

    const interaction = await ai.interactions.create({
        model: 'gemini-3-flash-preview',
        input: [
            { type: "document", uri: file.uri, mimeType: file.mimeType },
            { type: "text", text: "Summarize this document" }
        ],
    });

    console.log(interaction.steps.at(-1).content[0].text);

}

main();

REST

PDF_PATH="https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf"
DISPLAY_NAME="A17_FlightPlan"
PROMPT="Summarize this document"

# Download the PDF from the provided URL
wget -O "${DISPLAY_NAME}.pdf" "${PDF_PATH}"

MIME_TYPE=$(file -b --mime-type "${DISPLAY_NAME}.pdf")
NUM_BYTES=$(wc -c < "${DISPLAY_NAME}.pdf")

echo "MIME_TYPE: ${MIME_TYPE}"
echo "NUM_BYTES: ${NUM_BYTES}"

tmp_header_file=upload-header.tmp

# Initial resumable request defining metadata.
# The upload url is in the response headers dump them to a file.
curl "https://generativelanguage.googleapis.com/upload/v1beta/files?key=${GOOGLE_API_KEY}" \
  -D upload-header.tmp \
  -H "X-Goog-Upload-Protocol: resumable" \
  -H "X-Goog-Upload-Command: start" \
  -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \
  -H "X-Goog-Upload-Header-Content-Type: ${MIME_TYPE}" \
  -H "Content-Type: application/json" \
  -d "{'file': {'display_name': '${DISPLAY_NAME}'}}" 2> /dev/null

upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r")
rm "${tmp_header_file}"

# Upload the actual bytes.
curl "${upload_url}" \
  -H "Content-Length: ${NUM_BYTES}" \
  -H "X-Goog-Upload-Offset: 0" \
  -H "X-Goog-Upload-Command: upload, finalize" \
  --data-binary "@${DISPLAY_NAME}.pdf" 2> /dev/null > file_info.json

file_uri=$(jq ".file.uri" file_info.json)
echo "file_uri: ${file_uri}"

# Now create an interaction using that file
curl "https://generativelanguage.googleapis.com/v1beta/interactions" \
    -H "x-goog-api-key: $GOOGLE_API_KEY" \
    -H 'Content-Type: application/json' \
    -X POST \
    -d '{
      "model": "gemini-3-flash-preview",
      "input": [
        {"type": "text", "text": "'$PROMPT'"},
        {"type": "document", "uri": '$file_uri', "mimeType": "application/pdf"}
      ]
    }' 2> /dev/null > response.json

cat response.json
echo

jq ".steps[-1].content[0].text" response.json

# Clean up the downloaded PDF
rm "${DISPLAY_NAME}.pdf"

本地存储的大型 PDF

Python

from google import genai
import pathlib

client = genai.Client()

# Upload the PDF using the File API
file_path = pathlib.Path('large_file.pdf')
sample_file = client.files.upload(
    file=file_path,
)

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {"type": "document", "uri": sample_file.uri, "mime_type": sample_file.mime_type},
        {"type": "text", "text": "Summarize this document"}
    ]
)
print(interaction.steps[-1].content[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
    const file = await ai.files.upload({
        file: 'path-to-localfile.pdf',
        config: {
            displayName: 'A17_FlightPlan.pdf',
        },
    });

    // Wait for the file to be processed.
    let getFile = await ai.files.get({ name: file.name });
    while (getFile.state === 'PROCESSING') {
        getFile = await ai.files.get({ name: file.name });
        console.log(`current file status: ${getFile.state}`);
        console.log('File is still processing, retrying in 5 seconds');

        await new Promise((resolve) => {
            setTimeout(resolve, 5000);
        });
    }
    if (file.state === 'FAILED') {
        throw new Error('File processing failed.');
    }

    const interaction = await ai.interactions.create({
        model: 'gemini-3-flash-preview',
        input: [
            { type: "document", uri: file.uri, mimeType: file.mimeType },
            { type: "text", text: "Summarize this document" }
        ],
    });

    console.log(interaction.steps.at(-1).content[0].text);

}

main();

REST

PDF_PATH="path/to/large_file.pdf"
NUM_BYTES=$(wc -c < "${PDF_PATH}")
DISPLAY_NAME=TEXT
tmp_header_file=upload-header.tmp

# Initial resumable request defining metadata.
# The upload url is in the response headers dump them to a file.
curl "https://generativelanguage.googleapis.com/upload/v1beta/files?key=${GEMINI_API_KEY}" \
  -D upload-header.tmp \
  -H "X-Goog-Upload-Protocol: resumable" \
  -H "X-Goog-Upload-Command: start" \
  -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \
  -H "X-Goog-Upload-Header-Content-Type: application/pdf" \
  -H "Content-Type: application/json" \
  -d "{'file': {'display_name': '${DISPLAY_NAME}'}}" 2> /dev/null

upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r")
rm "${tmp_header_file}"

# Upload the actual bytes.
curl "${upload_url}" \
  -H "Content-Length: ${NUM_BYTES}" \
  -H "X-Goog-Upload-Offset: 0" \
  -H "X-Goog-Upload-Command: upload, finalize" \
  --data-binary "@${PDF_PATH}" 2> /dev/null > file_info.json

file_uri=$(jq ".file.uri" file_info.json)
echo file_uri=$file_uri

# Now create an interaction using that file
curl "https://generativelanguage.googleapis.com/v1beta/interactions" \
    -H "x-goog-api-key: $GEMINI_API_KEY" \
    -H 'Content-Type: application/json' \
    -X POST \
    -d '{
      "model": "gemini-3-flash-preview",
      "input": [
        {"type": "document", "uri": '$file_uri', "mimeType": "application/pdf"},
        {"type": "text", "text": "Can you add a few more lines to this poem?"}
      ]
    }' 2> /dev/null > response.json

cat response.json
echo

jq ".steps[-1].content[0].text" response.json

您可以调用 files.get 来验证 API 是否已成功存储上传的文件并获取其元数据。只有 name(以及扩展的 uri)是唯一的。

Python

from google import genai
import pathlib

client = genai.Client()

fpath = pathlib.Path('example.pdf')
fpath.write_text('hello')

file = client.files.upload(file='example.pdf')

file_info = client.files.get(name=file.name)
print(file_info.model_dump_json(indent=4))

REST

name=$(jq ".file.name" file_info.json)
# Get the file of interest to check state
curl https://generativelanguage.googleapis.com/v1beta/files/$name?key=$GEMINI_API_KEY > file_info.json
# Print some information about the file you got
name=$(jq ".file.name" file_info.json)
echo name=$name
file_uri=$(jq ".file.uri" file_info.json)
echo file_uri=$file_uri

传递多个 PDF

Gemini API 能够在单个请求中处理多个 PDF 文档(最多 1, 000 页),前提是文档和文本提示的总大小不超过模型的上下文窗口大小。

Python

from google import genai
import io
import httpx

client = genai.Client()

doc_url_1 = "https://arxiv.org/pdf/2312.11805"
doc_url_2 = "https://arxiv.org/pdf/2403.05530"

# Retrieve and upload both PDFs using the File API
doc_data_1 = io.BytesIO(httpx.get(doc_url_1).content)
doc_data_2 = io.BytesIO(httpx.get(doc_url_2).content)

sample_pdf_1 = client.files.upload(
  file=doc_data_1,
  config=dict(mime_type='application/pdf')
)
sample_pdf_2 = client.files.upload(
  file=doc_data_2,
  config=dict(mime_type='application/pdf')
)

prompt = "What is the difference between each of the main benchmarks between these two papers? Output these in a table."

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {"type": "document", "uri": sample_pdf_1.uri, "mime_type": sample_pdf_1.mime_type},
        {"type": "document", "uri": sample_pdf_2.uri, "mime_type": sample_pdf_2.mime_type},
        {"type": "text", "text": prompt}
    ]
)

print(interaction.steps[-1].content[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function uploadRemotePDF(url, displayName) {
    const pdfBuffer = await fetch(url)
        .then((response) => response.arrayBuffer());

    const fileBlob = new Blob([pdfBuffer], { type: 'application/pdf' });

    const file = await ai.files.upload({
        file: fileBlob,
        config: {
            displayName: displayName,
        },
    });

    // Wait for the file to be processed.
    let getFile = await ai.files.get({ name: file.name });
    while (getFile.state === 'PROCESSING') {
        getFile = await ai.files.get({ name: file.name });
        console.log(`current file status: ${getFile.state}`);
        console.log('File is still processing, retrying in 5 seconds');

        await new Promise((resolve) => {
            setTimeout(resolve, 5000);
        });
    }
    if (file.state === 'FAILED') {
        throw new Error('File processing failed.');
    }

    return file;
}

async function main() {
    const file1 = await uploadRemotePDF("https://arxiv.org/pdf/2312.11805", "PDF 1");
    const file2 = await uploadRemotePDF("https://arxiv.org/pdf/2403.05530", "PDF 2");

    const interaction = await ai.interactions.create({
        model: 'gemini-3-flash-preview',
        input: [
            { type: "document", uri: file1.uri, mimeType: file1.mimeType },
            { type: "document", uri: file2.uri, mimeType: file2.mimeType },
            { type: "text", text: "What is the difference between each of the main benchmarks between these two papers? Output these in a table." }
        ],
    });

    console.log(interaction.steps.at(-1).content[0].text);
}

main();

REST

DOC_URL_1="https://arxiv.org/pdf/2312.11805"
DOC_URL_2="https://arxiv.org/pdf/2403.05530"
DISPLAY_NAME_1="Gemini_paper"
DISPLAY_NAME_2="Gemini_1.5_paper"
PROMPT="What is the difference between each of the main benchmarks between these two papers? Output these in a table."

# Function to download and upload a PDF
upload_pdf() {
  local doc_url="$1"
  local display_name="$2"

  # Download the PDF
  wget -O "${display_name}.pdf" "${doc_url}"

  local MIME_TYPE=$(file -b --mime-type "${display_name}.pdf")
  local NUM_BYTES=$(wc -c < "${display_name}.pdf")

  echo "MIME_TYPE: ${MIME_TYPE}"
  echo "NUM_BYTES: ${NUM_BYTES}"

  local tmp_header_file=upload-header.tmp

  # Initial resumable request
  curl "https://generativelanguage.googleapis.com/upload/v1beta/files?key=${GOOGLE_API_KEY}" \
    -D "${tmp_header_file}" \
    -H "X-Goog-Upload-Protocol: resumable" \
    -H "X-Goog-Upload-Command: start" \
    -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \
    -H "X-Goog-Upload-Header-Content-Type: ${MIME_TYPE}" \
    -H "Content-Type: application/json" \
    -d "{'file': {'display_name': '${display_name}'}}" 2> /dev/null

  local upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r")
  rm "${tmp_header_file}"

  # Upload the PDF
  curl "${upload_url}" \
    -H "Content-Length: ${NUM_BYTES}" \
    -H "X-Goog-Upload-Offset: 0" \
    -H "X-Goog-Upload-Command: upload, finalize" \
    --data-binary "@${display_name}.pdf" 2> /dev/null > "file_info_${display_name}.json"

  local file_uri=$(jq ".file.uri" "file_info_${display_name}.json")
  echo "file_uri for ${display_name}: ${file_uri}"

  # Clean up the downloaded PDF
  rm "${display_name}.pdf"

  echo "${file_uri}"
}

# Upload the first PDF
file_uri_1=$(upload_pdf "${DOC_URL_1}" "${DISPLAY_NAME_1}")

# Upload the second PDF
file_uri_2=$(upload_pdf "${DOC_URL_2}" "${DISPLAY_NAME_2}")

# Now create an interaction using both files
curl "https://generativelanguage.googleapis.com/v1beta/interactions" \
    -H "x-goog-api-key: $GOOGLE_API_KEY" \
    -H 'Content-Type: application/json' \
    -X POST \
    -d '{
      "model": "gemini-3-flash-preview",
      "input": [
        {"type": "document", "uri": '$file_uri_1', "mimeType": "application/pdf"},
        {"type": "document", "uri": '$file_uri_2', "mimeType": "application/pdf"},
        {"type": "text", "text": "'$PROMPT'"}
      ]
    }' 2> /dev/null > response.json

cat response.json
echo

jq ".steps[-1].content[0].text" response.json

技术详情

Gemini 支持不超过 50MB 或 1,000 页的 PDF 文件。此限制适用于内嵌数据和 Files API 上传。每个文档页面相当于 258 个词元。

虽然除了模型的上下文窗口之外,文档中的像素数量没有具体限制,但较大的页面会被缩小到最大分辨率 (3072 x 3072),同时保留其原始宽高比,而较小的页面会被放大到 768 x 768 像素。除了带宽之外,较低尺寸的网页不会降低费用,而较高分辨率的网页也不会提高性能。

Gemini 3 模型

Gemini 3 引入了 media_resolution 参数,可对多模态视觉处理进行精细控制。您现在可以为每个媒体部分单独设置低、中或高分辨率。添加此功能后,PDF 文档的处理方式已更新:

  1. 原生文本收录:提取 PDF 中原生嵌入的文本并将其提供给模型。
  2. 结算和代币报告
    • 无需支付 PDF 中提取的原生文本所对应的 token 费用。
    • 在 API 响应的 usage_metadata 部分,通过处理 PDF 页面(作为图片)生成的令牌现在计入 IMAGE 模态,而不是像某些早期版本那样计入单独的 DOCUMENT 模态。

文档类型

从技术上讲,您可以传递其他 MIME 类型以进行文档理解,例如 TXT、Markdown、HTML、XML 等。不过,文档视觉 仅能有意义地理解 PDF。其他类型的文件将被提取为纯文本,模型将无法解读我们在这些文件的呈现中看到的内容。所有特定于文件类型的信息(例如图表、示意图、HTML 标记、Markdown 格式等)都将丢失。

如需了解其他文件输入方法,请参阅文件输入方法指南。

最佳做法

为了达到最佳效果,请注意以下事项:

  • 请先将页面旋转到正确方向,然后再上传。
  • 避免页面模糊不清。
  • 如果使用单页,请将文本提示放在该页之后。

后续步骤

如需了解详情,请参阅以下资源:

  • 文件提示策略:Gemini API 支持使用文本、图片、音频和视频数据进行提示,也称为多模态提示。
  • 系统指令:系统指令可让您根据自己的特定需求和使用情形来控制模型的行为。