[libav-devel] [PATCH 23/57] gsm: implement new audio decoding API

Justin Ruggles justin.ruggles at gmail.com
Sat Nov 26 23:06:34 CET 2011


---
 libavcodec/gsmdec.c      |   32 ++++++++++++++++++++++----------
 libavcodec/gsmdec_data.h |    2 ++
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/libavcodec/gsmdec.c b/libavcodec/gsmdec.c
index 1091745..97b6fe8 100644
--- a/libavcodec/gsmdec.c
+++ b/libavcodec/gsmdec.c
@@ -32,6 +32,8 @@
 
 static av_cold int gsm_init(AVCodecContext *avctx)
 {
+    GSMContext *s = avctx->priv_data;
+
     avctx->channels = 1;
     if (!avctx->sample_rate)
         avctx->sample_rate = 8000;
@@ -47,30 +49,35 @@ static av_cold int gsm_init(AVCodecContext *avctx)
         avctx->block_align = GSM_MS_BLOCK_SIZE;
     }
 
+    avcodec_get_frame_defaults(&s->frame);
+    avctx->coded_frame = &s->frame;
+
     return 0;
 }
 
 static int gsm_decode_frame(AVCodecContext *avctx, void *data,
-                            int *data_size, AVPacket *avpkt)
+                            int *got_frame_ptr, AVPacket *avpkt)
 {
+    GSMContext *s = avctx->priv_data;
     int res;
     GetBitContext gb;
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
-    int16_t *samples = data;
-    int frame_bytes = avctx->frame_size *
-                      av_get_bytes_per_sample(avctx->sample_fmt);
-
-    if (*data_size < frame_bytes) {
-        av_log(avctx, AV_LOG_ERROR, "Output buffer is too small\n");
-        return AVERROR(EINVAL);
-    }
+    int16_t *samples;
 
     if (buf_size < avctx->block_align) {
         av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
         return AVERROR_INVALIDDATA;
     }
 
+    /* get output buffer */
+    s->frame.nb_samples = avctx->frame_size;
+    if ((res = avctx->get_buffer(avctx, &s->frame)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return res;
+    }
+    samples = (int16_t *)s->frame.data[0];
+
     switch (avctx->codec_id) {
     case CODEC_ID_GSM:
         init_get_bits(&gb, buf, buf_size * 8);
@@ -85,7 +92,10 @@ static int gsm_decode_frame(AVCodecContext *avctx, void *data,
         if (res < 0)
             return res;
     }
-    *data_size = frame_bytes;
+
+    *got_frame_ptr   = 1;
+    *(AVFrame *)data = s->frame;
+
     return avctx->block_align;
 }
 
@@ -103,6 +113,7 @@ AVCodec ff_gsm_decoder = {
     .init           = gsm_init,
     .decode         = gsm_decode_frame,
     .flush          = gsm_flush,
+    .capabilities   = CODEC_CAP_DR1,
     .long_name = NULL_IF_CONFIG_SMALL("GSM"),
 };
 
@@ -114,5 +125,6 @@ AVCodec ff_gsm_ms_decoder = {
     .init           = gsm_init,
     .decode         = gsm_decode_frame,
     .flush          = gsm_flush,
+    .capabilities   = CODEC_CAP_DR1,
     .long_name = NULL_IF_CONFIG_SMALL("GSM Microsoft variant"),
 };
diff --git a/libavcodec/gsmdec_data.h b/libavcodec/gsmdec_data.h
index b78daa7..21789f7 100644
--- a/libavcodec/gsmdec_data.h
+++ b/libavcodec/gsmdec_data.h
@@ -23,6 +23,7 @@
 #define AVCODEC_GSMDEC_DATA
 
 #include <stdint.h>
+#include "avcodec.h"
 
 // input and output sizes in byte
 #define GSM_BLOCK_SIZE    33
@@ -30,6 +31,7 @@
 #define GSM_FRAME_SIZE   160
 
 typedef struct {
+    AVFrame frame;
     // Contains first 120 elements from the previous frame
     // (used by long_term_synth according to the "lag"),
     // then in the following 160 elements the current
-- 
1.7.1



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