1 files changed, 83 insertions, 20 deletions

diff --git a/libavcodec/g722enc.c b/libavcodec/g722enc.c
index 1eed784a72..1cb0070649 100644
--- a/libavcodec/g722enc.c
+++ b/libavcodec/g722enc.c
@@ -32,6 +32,15 @@
 
 #define FREEZE_INTERVAL 128
 
+/* This is an arbitrary value. Allowing insanely large values leads to strange
+   problems, so we limit it to a reasonable value */
+#define MAX_FRAME_SIZE 32768
+
+/* We clip the value of avctx->trellis to prevent data type overflows and
+   undefined behavior. Using larger values is insanely slow anyway. */
+#define MIN_TRELLIS 0
+#define MAX_TRELLIS 16
+
 static av_cold int g722_encode_init(AVCodecContext * avctx)
 {
     G722Context *c = avctx->priv_data;
@@ -56,6 +65,40 @@ static av_cold int g722_encode_init(AVCodecContext * avctx)
         }
     }
 
+    if (avctx->frame_size) {
+        /* validate frame size */
+        if (avctx->frame_size & 1 || avctx->frame_size > MAX_FRAME_SIZE) {
+            int new_frame_size;
+
+            if (avctx->frame_size == 1)
+                new_frame_size = 2;
+            else if (avctx->frame_size > MAX_FRAME_SIZE)
+                new_frame_size = MAX_FRAME_SIZE;
+            else
+                new_frame_size = avctx->frame_size - 1;
+
+            av_log(avctx, AV_LOG_WARNING, "Requested frame size is not "
+                   "allowed. Using %d instead of %d\n", new_frame_size,
+                   avctx->frame_size);
+            avctx->frame_size = new_frame_size;
+        }
+    } else {
+        /* This is arbitrary. We use 320 because it's 20ms @ 16kHz, which is
+           a common packet size for VoIP applications */
+        avctx->frame_size = 320;
+    }
+
+    if (avctx->trellis) {
+        /* validate trellis */
+        if (avctx->trellis < MIN_TRELLIS || avctx->trellis > MAX_TRELLIS) {
+            int new_trellis = av_clip(avctx->trellis, MIN_TRELLIS, MAX_TRELLIS);
+            av_log(avctx, AV_LOG_WARNING, "Requested trellis value is not "
+                   "allowed. Using %d instead of %d\n", new_trellis,
+                   avctx->trellis);
+            avctx->trellis = new_trellis;
+        }
+    }
+
     return 0;
 }
 
@@ -117,13 +160,12 @@ static inline int encode_low(const struct G722Band* state, int xlow)
     return (diff < 0 ? (i < 2 ? 63 : 33) : 61) - i;
 }
 
-static int g722_encode_trellis(AVCodecContext *avctx,
-                               uint8_t *dst, int buf_size, void *data)
+static void g722_encode_trellis(G722Context *c, int trellis,
+                                uint8_t *dst, int nb_samples,
+                                const int16_t *samples)
 {
-    G722Context *c = avctx->priv_data;
-    const int16_t *samples = data;
     int i, j, k;
-    int frontier = 1 << avctx->trellis;
+    int frontier = 1 << trellis;
     struct TrellisNode **nodes[2];
     struct TrellisNode **nodes_next[2];
     int pathn[2] = {0, 0}, froze = -1;
@@ -139,7 +181,7 @@ static int g722_encode_trellis(AVCodecContext *avctx,
         nodes[i][0]->state = c->band[i];
     }
 
-    for (i = 0; i < buf_size; i++) {
+    for (i = 0; i < nb_samples >> 1; i++) {
         int xlow, xhigh;
         struct TrellisNode *next[2];
         int heap_pos[2] = {0, 0};
@@ -271,8 +313,28 @@ static int g722_encode_trellis(AVCodecContext *avctx,
     }
     c->band[0] = nodes[0][0]->state;
     c->band[1] = nodes[1][0]->state;
+}
+
+static av_always_inline void encode_byte(G722Context *c, uint8_t *dst,
+                                         const int16_t *samples)
+{
+    int xlow, xhigh, ilow, ihigh;
+    filter_samples(c, samples, &xlow, &xhigh);
+    ihigh = encode_high(&c->band[1], xhigh);
+    ilow  = encode_low (&c->band[0], xlow);
+    ff_g722_update_high_predictor(&c->band[1], c->band[1].scale_factor *
+                                ff_g722_high_inv_quant[ihigh] >> 10, ihigh);
+    ff_g722_update_low_predictor(&c->band[0], ilow >> 2);
+    *dst = ihigh << 6 | ilow;
+}
 
-    return i;
+static void g722_encode_no_trellis(G722Context *c,
+                                   uint8_t *dst, int nb_samples,
+                                   const int16_t *samples)
+{
+    int i;
+    for (i = 0; i < nb_samples; i += 2)
+        encode_byte(c, dst++, &samples[i]);
 }
 
 static int g722_encode_frame(AVCodecContext *avctx,
@@ -280,22 +342,22 @@ static int g722_encode_frame(AVCodecContext *avctx,
 {
     G722Context *c = avctx->priv_data;
     const int16_t *samples = data;
-    int i;
+    int nb_samples;
 
-    if (avctx->trellis)
-        return g722_encode_trellis(avctx, dst, buf_size, data);
+    nb_samples = avctx->frame_size - (avctx->frame_size & 1);
 
-    for (i = 0; i < buf_size; i++) {
-        int xlow, xhigh, ihigh, ilow;
-        filter_samples(c, &samples[2*i], &xlow, &xhigh);
-        ihigh = encode_high(&c->band[1], xhigh);
-        ilow  = encode_low(&c->band[0], xlow);
-        ff_g722_update_high_predictor(&c->band[1], c->band[1].scale_factor *
-                                      ff_g722_high_inv_quant[ihigh] >> 10, ihigh);
-        ff_g722_update_low_predictor(&c->band[0], ilow >> 2);
-        *dst++ = ihigh << 6 | ilow;
+    if (avctx->trellis)
+        g722_encode_trellis(c, avctx->trellis, dst, nb_samples, samples);
+    else
+        g722_encode_no_trellis(c, dst, nb_samples, samples);
+
+    /* handle last frame with odd frame_size */
+    if (nb_samples < avctx->frame_size) {
+        int16_t last_samples[2] = { samples[nb_samples], samples[nb_samples] };
+        encode_byte(c, &dst[nb_samples >> 1], last_samples);
     }
-    return i;
+
+    return (avctx->frame_size + 1) >> 1;
 }
 
 AVCodec ff_adpcm_g722_encoder = {
@@ -306,6 +368,7 @@ AVCodec ff_adpcm_g722_encoder = {
     .init           = g722_encode_init,
     .close          = g722_encode_close,
     .encode         = g722_encode_frame,
+    .capabilities   = CODEC_CAP_SMALL_LAST_FRAME,
     .long_name      = NULL_IF_CONFIG_SMALL("G.722 ADPCM"),
     .sample_fmts    = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
 };