@@ -58,6 +58,79 @@ static int alloc_and_copy(uint8_t **poutbuf, int *poutbuf_size,

     return 0;

 }

+static int h264_extradata_to_annexb(AVCodecContext *avctx, const int padding)

+{

+    uint16_t unit_size;

+    uint64_t total_size                 = 0;

+    uint8_t *out                        = NULL, unit_nb, sps_done = 0,

+             sps_seen                   = 0, pps_seen = 0;

+    const uint8_t *extradata            = avctx->extradata + 4;

+    static const uint8_t nalu_header[4] = { 0, 0, 0, 1 };

+    int length_size = (*extradata++ & 0x3) + 1; // retrieve length coded size

+

+    if (length_size == 3)

+        return AVERROR(EINVAL);

+

+    /* retrieve sps and pps unit(s) */

+    unit_nb = *extradata++ & 0x1f; /* number of sps unit(s) */

+    if (!unit_nb) {

+        unit_nb = *extradata++; /* number of pps unit(s) */

+        sps_done++;

+

+        if (unit_nb)

+            pps_seen = 1;

+    } else {

+        sps_seen = 1;

+    }

+

+    while (unit_nb--) {

+        void *tmp;

+

+        unit_size   = AV_RB16(extradata);

+        total_size += unit_size + 4;

+        if (total_size > INT_MAX - padding ||

+            extradata + 2 + unit_size > avctx->extradata +

+            avctx->extradata_size) {

+            av_free(out);

+            return AVERROR(EINVAL);

+        }

+        tmp = av_realloc(out, total_size + padding);

+        if (!tmp) {

+            av_free(out);

+            return AVERROR(ENOMEM);

+        }

+        out = tmp;

+        memcpy(out + total_size - unit_size - 4, nalu_header, 4);

+        memcpy(out + total_size - unit_size, extradata + 2, unit_size);

+        extradata += 2 + unit_size;

+

+        if (!unit_nb && !sps_done++) {

+            unit_nb = *extradata++; /* number of pps unit(s) */

+            if (unit_nb)

+                pps_seen = 1;

+        }

+    }

+

+    if (out)

+        memset(out + total_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

+

+    if (!sps_seen)

+        av_log(avctx, AV_LOG_WARNING,

+               "Warning: SPS NALU missing or invalid. "

+               "The resulting stream may not play.\n");

+

+    if (!pps_seen)

+        av_log(avctx, AV_LOG_WARNING,

+               "Warning: PPS NALU missing or invalid. "

+               "The resulting stream may not play.\n");

+

+    av_free(avctx->extradata);

+    avctx->extradata      = out;

+    avctx->extradata_size = total_size;

+

+    return length_size;

+}

+

 static int h264_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,

                                    AVCodecContext *avctx, const char *args,

                                    uint8_t **poutbuf, int *poutbuf_size,

@@ -69,6 +142,7 @@ static int h264_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,

     int32_t nal_size;

     uint32_t cumul_size    = 0;

     const uint8_t *buf_end = buf + buf_size;

+    int ret = 0;

     /* nothing to filter */

     if (!avctx->extradata || avctx->extradata_size < 6) {

@@ -79,74 +153,10 @@ static int h264_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,

     /* retrieve sps and pps NAL units from extradata */

     if (!ctx->extradata_parsed) {

-        uint16_t unit_size;

-        uint64_t total_size                 = 0;

-        uint8_t *out                        = NULL, unit_nb, sps_done = 0,

-                 sps_seen                   = 0, pps_seen = 0;

-        const uint8_t *extradata            = avctx->extradata + 4;

-        static const uint8_t nalu_header[4] = { 0, 0, 0, 1 };

-

-        /* retrieve length coded size */

-        ctx->length_size = (*extradata++ & 0x3) + 1;

-        if (ctx->length_size == 3)

-            return AVERROR(EINVAL);

-

-        /* retrieve sps and pps unit(s) */

-        unit_nb = *extradata++ & 0x1f; /* number of sps unit(s) */

-        if (!unit_nb) {

-            unit_nb = *extradata++; /* number of pps unit(s) */

-            sps_done++;

-

-            if (unit_nb)

-                pps_seen = 1;

-        } else {

-            sps_seen = 1;

-        }

-

-        while (unit_nb--) {

-            void *tmp;

-

-            unit_size   = AV_RB16(extradata);

-            total_size += unit_size + 4;

-            if (total_size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE ||

-                extradata + 2 + unit_size > avctx->extradata +

-                avctx->extradata_size) {

-                av_free(out);

-                return AVERROR(EINVAL);

-            }

-            tmp = av_realloc(out, total_size + FF_INPUT_BUFFER_PADDING_SIZE);

-            if (!tmp) {

-                av_free(out);

-                return AVERROR(ENOMEM);

-            }

-            out = tmp;

-            memcpy(out + total_size - unit_size - 4, nalu_header, 4);

-            memcpy(out + total_size - unit_size, extradata + 2, unit_size);

-            extradata += 2 + unit_size;

-

-            if (!unit_nb && !sps_done++) {

-                unit_nb = *extradata++; /* number of pps unit(s) */

-                if (unit_nb)

-                    pps_seen = 1;

-            }

-        }

-

-        if (out)

-            memset(out + total_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

-

-        if (!sps_seen)

-            av_log(avctx, AV_LOG_WARNING,

-                   "Warning: SPS NALU missing or invalid. "

-                   "The resulting stream may not play.\n");

-

-        if (!pps_seen)

-            av_log(avctx, AV_LOG_WARNING,

-                   "Warning: PPS NALU missing or invalid. "

-                   "The resulting stream may not play.\n");

-

-        av_free(avctx->extradata);

-        avctx->extradata      = out;

-        avctx->extradata_size = total_size;

+        ret = h264_extradata_to_annexb(avctx, FF_INPUT_BUFFER_PADDING_SIZE);

+        if (ret < 0)

+            return ret;

+        ctx->length_size      = ret;

         ctx->first_idr        = 1;

         ctx->extradata_parsed = 1;

     }