From 5cd597f22ff5b1587e005153ad5bd33ecf6907c8 Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justin.ruggles@gmail.com>
Date: Sun, 23 Dec 2012 16:56:17 -0500
Subject: [PATCH] alac: decode directly to the user-provided AVFrame

---
 libavcodec/alac.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/libavcodec/alac.c b/libavcodec/alac.c
index 1a3f769..0c5bdd3 100644
--- a/libavcodec/alac.c
+++ b/libavcodec/alac.c
@@ -58,7 +58,6 @@
 
 typedef struct {
     AVCodecContext *avctx;
-    AVFrame frame;
     GetBitContext gb;
     int channels;
 
@@ -248,7 +247,7 @@ static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
             buffer[ch][i] = (buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i];
 }
 
-static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
+static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
                           int channels)
 {
     ALACContext *alac = avctx->priv_data;
@@ -283,8 +282,8 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
     }
     if (!alac->nb_samples) {
         /* get output buffer */
-        alac->frame.nb_samples = output_samples;
-        if ((ret = ff_get_buffer(avctx, &alac->frame)) < 0) {
+        frame->nb_samples = output_samples;
+        if ((ret = ff_get_buffer(avctx, frame)) < 0) {
             av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
             return ret;
         }
@@ -296,7 +295,7 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
     alac->nb_samples = output_samples;
     if (alac->sample_size > 16) {
         for (ch = 0; ch < channels; ch++)
-            alac->output_samples_buffer[ch] = (int32_t *)alac->frame.extended_data[ch_index + ch];
+            alac->output_samples_buffer[ch] = (int32_t *)frame->extended_data[ch_index + ch];
     }
 
     if (is_compressed) {
@@ -377,7 +376,7 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
     switch(alac->sample_size) {
     case 16: {
         for (ch = 0; ch < channels; ch++) {
-            int16_t *outbuffer = (int16_t *)alac->frame.extended_data[ch_index + ch];
+            int16_t *outbuffer = (int16_t *)frame->extended_data[ch_index + ch];
             for (i = 0; i < alac->nb_samples; i++)
                 *outbuffer++ = alac->output_samples_buffer[ch][i];
         }}
@@ -397,6 +396,7 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
                              int *got_frame_ptr, AVPacket *avpkt)
 {
     ALACContext *alac = avctx->priv_data;
+    AVFrame *frame    = data;
     enum AlacRawDataBlockType element;
     int channels;
     int ch, ret, got_end;
@@ -423,7 +423,7 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
             return AVERROR_INVALIDDATA;
         }
 
-        ret = decode_element(avctx, data,
+        ret = decode_element(avctx, frame,
                              ff_alac_channel_layout_offsets[alac->channels - 1][ch],
                              channels);
         if (ret < 0 && get_bits_left(&alac->gb))
@@ -441,8 +441,7 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
                avpkt->size * 8 - get_bits_count(&alac->gb));
     }
 
-    *got_frame_ptr   = 1;
-    *(AVFrame *)data = alac->frame;
+    *got_frame_ptr = 1;
 
     return avpkt->size;
 }
@@ -563,9 +562,6 @@ static av_cold int alac_decode_init(AVCodecContext * avctx)
         return ret;
     }
 
-    avcodec_get_frame_defaults(&alac->frame);
-    avctx->coded_frame = &alac->frame;
-
     return 0;
 }
 
-- 
2.7.4