fix(media): 转码按短边等比定档并回写实际尺寸

docs/plans/PROGRESS.md

@@ -25421,3 +25421,42 @@ expected: "1:1"
 小源码片仍被放大，且未固定 SAR。横屏基础尺寸用例已通过，说明测试片生成、
 ffprobe 探测与 HLS 链路本身正常。
 
+### 实现
+
+- ffprobe 读取源视频 width/height；存在 90/270 度旋转元数据时按最终显示方向交换宽高。
+- 每档短边值取 `min(档位 width/height, 源显示短边)`，再向下取偶数。
+- 横屏使用 `scale=-2:<short>:flags=lanczos,setsar=1`；
+  竖屏使用 `scale=<short>:-2:flags=lanczos,setsar=1`，只等比缩放。
+- 不放大策略统一为“高于源短边的档位仍保留 quality 与码率，分辨率封顶到源短边”，
+  因而不会出现全部档位被跳过、无 rendition 可播的情况。
+- 每档完成后 ffprobe 读取 variant HLS 的实际 width/height，写入
+  `ProducedRendition`，worker 继续原样回写 `media_rendition`；
+  master playlist 的 RESOLUTION 也使用实际尺寸。
+
+### 定向测试
+
+```text
+$ mvn -pl fruitshorts-transcode-worker -am \
+  -Dtest=FfmpegTranscodeRunnerSmokeTest \
+  -Dsurefire.failIfNoSpecifiedTests=false test
+[INFO] Tests run: 4, Failures: 0, Errors: 0, Skipped: 0
+[INFO] BUILD SUCCESS
+```
+
+解读：横屏、竖屏、不放大、偶数尺寸、SAR=1、ffprobe 实际尺寸与
+master RESOLUTION 均通过真实 ffmpeg 验证。
+
+### 最终门禁
+
+```text
+$ mvn -pl fruitshorts-module-media,fruitshorts-transcode-worker test
+[INFO] Tests run: 8, Failures: 0, Errors: 0, Skipped: 0
+[INFO] Tests run: 35, Failures: 0, Errors: 0, Skipped: 0
+[INFO] fruitshorts-module-media ........................... SUCCESS
+[INFO] fruitshorts-transcode-worker ....................... SUCCESS
+[INFO] BUILD SUCCESS
+```
+
+解读：P2 查询测试、worker 入队/失败回写测试和新增宽高比 smoke 全部通过。
+未启停服务、未执行数据库变更、未改前端/App/specs 或 P2 接口字段。
+

fruitshorts-module-media/src/main/java/com/fruitshorts/media/service/transcode/FfmpegTranscodeRunner.java

@@ -45,10 +45,11 @@ public class FfmpegTranscodeRunner implements TranscodeRunner {
         }
         createDirectories(request.outputDir());
         int durationSec = probeDuration(request);
+        SourceDimensions source = probeSourceDimensions(request);
 
         List<ProducedRendition> renditions = new ArrayList<>(request.ladder().size());
         for (LadderRung rung : request.ladder()) {
-            renditions.add(transcodeRung(request, rung));
+            renditions.add(transcodeRung(request, rung, source));
         }
         writeMasterPlaylist(request, renditions);
         ProducedRendition poster = extractPoster(request);
@@ -60,17 +61,20 @@ public class FfmpegTranscodeRunner implements TranscodeRunner {
                 poster.objectKey(), durationSec, thumbnail);
     }
 
-    private ProducedRendition transcodeRung(TranscodeRequest request, LadderRung rung) {
+    private ProducedRendition transcodeRung(
+            TranscodeRequest request, LadderRung rung, SourceDimensions source) {
         String relativeDir = rung.quality() + "/";
         Path rungDir = request.outputDir().resolve(rung.quality());
         createDirectories(rungDir);
+        int shortEdge = effectiveShortEdge(rung, source);
+        String scaleFilter = source.landscape()
+                ? "scale=-2:" + shortEdge + ":flags=lanczos,setsar=1"
+                : "scale=" + shortEdge + ":-2:flags=lanczos,setsar=1";
         List<String> command = List.of(
                 request.ffmpegPath(), "-y",
                 "-i", request.sourceFile().toString(),
-                // 等比缩放到目标档位（不拉伸）。force_divisible_by=2 不能省：
+                // 按源方向只用短边定档；-2 保证自动推导的一边为偶数，setsar=1 避免播放器再次拉伸
-                // 640x360 的源在 854x480 档会算出 853x480 这种奇数宽度，libx264 直接拒绝（width not divisible by 2）
+                "-vf", scaleFilter,
-                "-vf", "scale=" + rung.width() + ":" + rung.height()
-                        + ":force_original_aspect_ratio=decrease:force_divisible_by=2",
                 "-c:v", "libx264", "-preset", "veryfast",
                 "-b:v", rung.videoBitrateKbps() + "k",
                 // 强制在每个分片边界插关键帧：只写 -hls_time 的话，片源关键帧间隔大于分片时长时
@@ -88,12 +92,19 @@ public class FfmpegTranscodeRunner implements TranscodeRunner {
             throw new ServiceException(ErrorCode.INTERNAL_ERROR,
                     "ffmpeg 未产出播放列表：" + playlist);
         }
-        return new ProducedRendition(rung.quality(), rung.width(), rung.height(),
+        Dimensions output = probeOutputDimensions(request, playlist);
+        return new ProducedRendition(rung.quality(), output.width(), output.height(),
                 rung.videoBitrateKbps(), rung.audioBitrateKbps(),
                 joinKey(request.objectKeyPrefix(), relativeDir + VARIANT_PLAYLIST),
                 sizeOf(rungDir), countSegments(rungDir));
     }
 
+    private int effectiveShortEdge(LadderRung rung, SourceDimensions source) {
+        int rungShortEdge = Math.min(rung.width(), rung.height());
+        int capped = Math.min(rungShortEdge, source.shortEdge());
+        return Math.max(2, capped - capped % 2);
+    }
+
     /** 手写 master.m3u8：按带宽升序，把每档的 index.m3u8 串起来。 */
     private void writeMasterPlaylist(TranscodeRequest request, List<ProducedRendition> renditions) {
         StringBuilder body = new StringBuilder("#EXTM3U\n#EXT-X-VERSION:3\n");
@@ -151,6 +162,91 @@ public class FfmpegTranscodeRunner implements TranscodeRunner {
         }
     }
 
+    /**
+     * ffprobe 同时读取编码尺寸和旋转信息；旋转 90/270 度时按最终显示方向交换宽高。
+     */
+    private SourceDimensions probeSourceDimensions(TranscodeRequest request) {
+        String output = runProcess(List.of(
+                request.ffprobePath(), "-v", "error",
+                "-select_streams", "v:0",
+                "-show_entries",
+                "stream=width,height:stream_side_data=rotation:stream_tags=rotate",
+                "-of", "default=noprint_wrappers=1",
+                request.sourceFile().toString()), 60, "探测视频尺寸失败");
+        int width = 0;
+        int height = 0;
+        Double sideRotation = null;
+        Double tagRotation = null;
+        for (String line : output.split("\\R")) {
+            String[] pair = line.trim().split("=", 2);
+            if (pair.length != 2) {
+                continue;
+            }
+            String key = pair[0];
+            String value = pair[1];
+            if ("width".equals(key)) {
+                width = parseInt(value);
+            } else if ("height".equals(key)) {
+                height = parseInt(value);
+            } else if ("rotation".equals(key)) {
+                sideRotation = parseDouble(value);
+            } else if ("TAG:rotate".equals(key)) {
+                tagRotation = parseDouble(value);
+            }
+        }
+        if (width <= 0 || height <= 0) {
+            throw new ServiceException(ErrorCode.INTERNAL_ERROR,
+                    "ffprobe 未返回有效视频尺寸：" + width + "x" + height);
+        }
+        double rotation = sideRotation != null
+                ? sideRotation : tagRotation == null ? 0 : tagRotation;
+        boolean quarterTurn = Math.abs(Math.round(rotation)) % 180 == 90;
+        return new SourceDimensions(
+                quarterTurn ? height : width,
+                quarterTurn ? width : height);
+    }
+
+    /** rendition 必须记录真实产物尺寸，不能沿用档位名义宽高。 */
+    private Dimensions probeOutputDimensions(TranscodeRequest request, Path playlist) {
+        String output = runProcess(List.of(
+                request.ffprobePath(), "-v", "error",
+                "-select_streams", "v:0",
+                "-show_entries", "stream=width,height",
+                "-of", "csv=s=x:p=0",
+                playlist.toString()), 60, "探测转码产物尺寸失败");
+        String first = output.lines().findFirst().orElse("").trim();
+        String[] pair = first.split("x");
+        if (pair.length != 2) {
+            throw new ServiceException(ErrorCode.INTERNAL_ERROR,
+                    "ffprobe 返回了无法解析的产物尺寸：" + first);
+        }
+        int width = parseInt(pair[0]);
+        int height = parseInt(pair[1]);
+        if (width <= 0 || height <= 0 || width % 2 != 0 || height % 2 != 0) {
+            throw new ServiceException(ErrorCode.INTERNAL_ERROR,
+                    "转码产物尺寸非法：" + width + "x" + height);
+        }
+        return new Dimensions(width, height);
+    }
+
+    private int parseInt(String value) {
+        try {
+            return Integer.parseInt(value.trim());
+        } catch (NumberFormatException ex) {
+            throw new ServiceException(ErrorCode.INTERNAL_ERROR,
+                    "ffprobe 返回了非法数字：" + value);
+        }
+    }
+
+    private double parseDouble(String value) {
+        try {
+            return Double.parseDouble(value.trim());
+        } catch (NumberFormatException ex) {
+            throw new ServiceException(ErrorCode.INTERNAL_ERROR,
+                    "ffprobe 返回了非法旋转角度：" + value);
+        }
+    }
+
     /**
      * 起进程并等结果；非 0 退出把输出尾部带进异常，方便定位是片源问题还是参数问题。
      *
@@ -235,4 +331,17 @@ public class FfmpegTranscodeRunner implements TranscodeRunner {
         String cleanPrefix = prefix == null ? "" : prefix.replaceAll("/+$", "");
         return cleanPrefix.isEmpty() ? relative : cleanPrefix + "/" + relative;
     }
+
+    private record SourceDimensions(int width, int height) {
+        private boolean landscape() {
+            return width >= height;
+        }
+
+        private int shortEdge() {
+            return Math.min(width, height);
+        }
+    }
+
+    private record Dimensions(int width, int height) {
+    }
 }