]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/alac.c
vaapi: mpeg2: fix slice_vertical_position calculation.
[ffmpeg] / libavcodec / alac.c
index eb6c1cfc161f541854330cd5e3b8b643c8014ada..ab9fb81d87ed236ffd77bd92bbc7f2364f01d460 100644 (file)
@@ -452,24 +452,29 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
                                         ricemodifier[ch] * alac->setinfo_rice_historymult / 4,
                                         (1 << alac->setinfo_rice_kmodifier) - 1);
 
-            if (prediction_type[ch] == 0) {
-                /* adaptive fir */
-                predictor_decompress_fir_adapt(alac->predicterror_buffer[ch],
-                                               alac->outputsamples_buffer[ch],
-                                               outputsamples,
-                                               readsamplesize,
-                                               predictor_coef_table[ch],
-                                               predictor_coef_num[ch],
-                                               prediction_quantitization[ch]);
-            } else {
-                av_log(avctx, AV_LOG_ERROR, "FIXME: unhandled prediction type: %i\n", prediction_type[ch]);
-                /* I think the only other prediction type (or perhaps this is
-                 * just a boolean?) runs adaptive fir twice.. like:
-                 * predictor_decompress_fir_adapt(predictor_error, tempout, ...)
-                 * predictor_decompress_fir_adapt(predictor_error, outputsamples ...)
-                 * little strange..
+            /* adaptive FIR filter */
+            if (prediction_type[ch] == 15) {
+                /* Prediction type 15 runs the adaptive FIR twice.
+                 * The first pass uses the special-case coef_num = 31, while
+                 * the second pass uses the coefs from the bitstream.
+                 *
+                 * However, this prediction type is not currently used by the
+                 * reference encoder.
                  */
+                predictor_decompress_fir_adapt(alac->predicterror_buffer[ch],
+                                               alac->predicterror_buffer[ch],
+                                               outputsamples, readsamplesize,
+                                               NULL, 31, 0);
+            } else if (prediction_type[ch] > 0) {
+                av_log(avctx, AV_LOG_WARNING, "unknown prediction type: %i\n",
+                       prediction_type[ch]);
             }
+            predictor_decompress_fir_adapt(alac->predicterror_buffer[ch],
+                                           alac->outputsamples_buffer[ch],
+                                           outputsamples, readsamplesize,
+                                           predictor_coef_table[ch],
+                                           predictor_coef_num[ch],
+                                           prediction_quantitization[ch]);
         }
     } else {
         /* not compressed, easy case */
@@ -566,29 +571,30 @@ buf_alloc_fail:
 
 static int alac_set_info(ALACContext *alac)
 {
-    const unsigned char *ptr = alac->avctx->extradata;
+    GetByteContext gb;
 
-    ptr += 4; /* size */
-    ptr += 4; /* alac */
-    ptr += 4; /* version */
+    bytestream2_init(&gb, alac->avctx->extradata,
+                     alac->avctx->extradata_size);
 
-    if(AV_RB32(ptr) >= UINT_MAX/4){
-        av_log(alac->avctx, AV_LOG_ERROR, "setinfo_max_samples_per_frame too large\n");
-        return -1;
-    }
+    bytestream2_skipu(&gb, 12); // size:4, alac:4, version:4
 
     /* buffer size / 2 ? */
-    alac->setinfo_max_samples_per_frame = bytestream_get_be32(&ptr);
-    ptr++;                          /* compatible version */
-    alac->setinfo_sample_size           = *ptr++;
-    alac->setinfo_rice_historymult      = *ptr++;
-    alac->setinfo_rice_initialhistory   = *ptr++;
-    alac->setinfo_rice_kmodifier        = *ptr++;
-    alac->numchannels                   = *ptr++;
-    bytestream_get_be16(&ptr);      /* maxRun */
-    bytestream_get_be32(&ptr);      /* max coded frame size */
-    bytestream_get_be32(&ptr);      /* average bitrate */
-    bytestream_get_be32(&ptr);      /* samplerate */
+    alac->setinfo_max_samples_per_frame = bytestream2_get_be32u(&gb);
+    if (alac->setinfo_max_samples_per_frame >= UINT_MAX/4){
+        av_log(alac->avctx, AV_LOG_ERROR,
+               "setinfo_max_samples_per_frame too large\n");
+        return AVERROR_INVALIDDATA;
+    }
+    bytestream2_skipu(&gb, 1);  // compatible version
+    alac->setinfo_sample_size           = bytestream2_get_byteu(&gb);
+    alac->setinfo_rice_historymult      = bytestream2_get_byteu(&gb);
+    alac->setinfo_rice_initialhistory   = bytestream2_get_byteu(&gb);
+    alac->setinfo_rice_kmodifier        = bytestream2_get_byteu(&gb);
+    alac->numchannels                   = bytestream2_get_byteu(&gb);
+    bytestream2_get_be16u(&gb); // maxRun
+    bytestream2_get_be32u(&gb); // max coded frame size
+    bytestream2_get_be32u(&gb); // average bitrate
+    bytestream2_get_be32u(&gb); // samplerate
 
     return 0;
 }
@@ -655,5 +661,5 @@ AVCodec ff_alac_decoder = {
     .close          = alac_decode_close,
     .decode         = alac_decode_frame,
     .capabilities   = CODEC_CAP_DR1,
-    .long_name = NULL_IF_CONFIG_SMALL("ALAC (Apple Lossless Audio Codec)"),
+    .long_name      = NULL_IF_CONFIG_SMALL("ALAC (Apple Lossless Audio Codec)"),
 };